b10695c8f1
The fast write mutex is intended to protect accounting, but it is redundant because all accounting is performed through atomic operations. It also serializes all metaslab IO behind a mutex, which introduces a theoretical scaling regression that the Illumos developers did not like when we showed this to them. Removing it makes the selection of the metaslab_group lock free as it is on Illumos. The selection is not quite the same without the lock because the loop races with IO completions, but any imbalances caused by this are likely to be corrected by subsequent metaslab group selections. Signed-off-by: Richard Yao <ryao@gentoo.org> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Closes #3643
2738 lines
77 KiB
C
2738 lines
77 KiB
C
/*
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* CDDL HEADER START
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*
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* The contents of this file are subject to the terms of the
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* Common Development and Distribution License (the "License").
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* You may not use this file except in compliance with the License.
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*
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* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
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* or http://www.opensolaris.org/os/licensing.
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* See the License for the specific language governing permissions
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* and limitations under the License.
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*
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* When distributing Covered Code, include this CDDL HEADER in each
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* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
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* If applicable, add the following below this CDDL HEADER, with the
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* fields enclosed by brackets "[]" replaced with your own identifying
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* information: Portions Copyright [yyyy] [name of copyright owner]
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*
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* CDDL HEADER END
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*/
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/*
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* Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
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* Copyright (c) 2011, 2015 by Delphix. All rights reserved.
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* Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
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*/
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#include <sys/zfs_context.h>
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#include <sys/dmu.h>
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#include <sys/dmu_tx.h>
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#include <sys/space_map.h>
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#include <sys/metaslab_impl.h>
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#include <sys/vdev_impl.h>
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#include <sys/zio.h>
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#include <sys/spa_impl.h>
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#include <sys/zfeature.h>
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#define WITH_DF_BLOCK_ALLOCATOR
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/*
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* Allow allocations to switch to gang blocks quickly. We do this to
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* avoid having to load lots of space_maps in a given txg. There are,
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* however, some cases where we want to avoid "fast" ganging and instead
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* we want to do an exhaustive search of all metaslabs on this device.
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* Currently we don't allow any gang, slog, or dump device related allocations
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* to "fast" gang.
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*/
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#define CAN_FASTGANG(flags) \
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(!((flags) & (METASLAB_GANG_CHILD | METASLAB_GANG_HEADER | \
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METASLAB_GANG_AVOID)))
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#define METASLAB_WEIGHT_PRIMARY (1ULL << 63)
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#define METASLAB_WEIGHT_SECONDARY (1ULL << 62)
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#define METASLAB_ACTIVE_MASK \
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(METASLAB_WEIGHT_PRIMARY | METASLAB_WEIGHT_SECONDARY)
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/*
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* Metaslab granularity, in bytes. This is roughly similar to what would be
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* referred to as the "stripe size" in traditional RAID arrays. In normal
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* operation, we will try to write this amount of data to a top-level vdev
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* before moving on to the next one.
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*/
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unsigned long metaslab_aliquot = 512 << 10;
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uint64_t metaslab_gang_bang = SPA_MAXBLOCKSIZE + 1; /* force gang blocks */
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/*
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* The in-core space map representation is more compact than its on-disk form.
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* The zfs_condense_pct determines how much more compact the in-core
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* space_map representation must be before we compact it on-disk.
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* Values should be greater than or equal to 100.
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*/
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int zfs_condense_pct = 200;
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/*
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* Condensing a metaslab is not guaranteed to actually reduce the amount of
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* space used on disk. In particular, a space map uses data in increments of
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* MAX(1 << ashift, space_map_blksz), so a metaslab might use the
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* same number of blocks after condensing. Since the goal of condensing is to
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* reduce the number of IOPs required to read the space map, we only want to
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* condense when we can be sure we will reduce the number of blocks used by the
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* space map. Unfortunately, we cannot precisely compute whether or not this is
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* the case in metaslab_should_condense since we are holding ms_lock. Instead,
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* we apply the following heuristic: do not condense a spacemap unless the
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* uncondensed size consumes greater than zfs_metaslab_condense_block_threshold
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* blocks.
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*/
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int zfs_metaslab_condense_block_threshold = 4;
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/*
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* The zfs_mg_noalloc_threshold defines which metaslab groups should
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* be eligible for allocation. The value is defined as a percentage of
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* free space. Metaslab groups that have more free space than
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* zfs_mg_noalloc_threshold are always eligible for allocations. Once
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* a metaslab group's free space is less than or equal to the
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* zfs_mg_noalloc_threshold the allocator will avoid allocating to that
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* group unless all groups in the pool have reached zfs_mg_noalloc_threshold.
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* Once all groups in the pool reach zfs_mg_noalloc_threshold then all
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* groups are allowed to accept allocations. Gang blocks are always
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* eligible to allocate on any metaslab group. The default value of 0 means
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* no metaslab group will be excluded based on this criterion.
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*/
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int zfs_mg_noalloc_threshold = 0;
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/*
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* Metaslab groups are considered eligible for allocations if their
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* fragmenation metric (measured as a percentage) is less than or equal to
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* zfs_mg_fragmentation_threshold. If a metaslab group exceeds this threshold
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* then it will be skipped unless all metaslab groups within the metaslab
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* class have also crossed this threshold.
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*/
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int zfs_mg_fragmentation_threshold = 85;
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/*
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* Allow metaslabs to keep their active state as long as their fragmentation
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* percentage is less than or equal to zfs_metaslab_fragmentation_threshold. An
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* active metaslab that exceeds this threshold will no longer keep its active
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* status allowing better metaslabs to be selected.
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*/
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int zfs_metaslab_fragmentation_threshold = 70;
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/*
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* When set will load all metaslabs when pool is first opened.
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*/
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int metaslab_debug_load = 0;
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/*
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* When set will prevent metaslabs from being unloaded.
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*/
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int metaslab_debug_unload = 0;
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/*
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* Minimum size which forces the dynamic allocator to change
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* it's allocation strategy. Once the space map cannot satisfy
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* an allocation of this size then it switches to using more
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* aggressive strategy (i.e search by size rather than offset).
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*/
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uint64_t metaslab_df_alloc_threshold = SPA_MAXBLOCKSIZE;
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/*
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* The minimum free space, in percent, which must be available
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* in a space map to continue allocations in a first-fit fashion.
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* Once the space_map's free space drops below this level we dynamically
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* switch to using best-fit allocations.
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*/
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int metaslab_df_free_pct = 4;
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/*
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* Percentage of all cpus that can be used by the metaslab taskq.
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*/
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int metaslab_load_pct = 50;
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/*
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* Determines how many txgs a metaslab may remain loaded without having any
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* allocations from it. As long as a metaslab continues to be used we will
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* keep it loaded.
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*/
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int metaslab_unload_delay = TXG_SIZE * 2;
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/*
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* Max number of metaslabs per group to preload.
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*/
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int metaslab_preload_limit = SPA_DVAS_PER_BP;
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/*
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* Enable/disable preloading of metaslab.
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*/
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int metaslab_preload_enabled = B_TRUE;
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/*
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* Enable/disable fragmentation weighting on metaslabs.
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*/
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int metaslab_fragmentation_factor_enabled = B_TRUE;
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/*
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* Enable/disable lba weighting (i.e. outer tracks are given preference).
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*/
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int metaslab_lba_weighting_enabled = B_TRUE;
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/*
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* Enable/disable metaslab group biasing.
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*/
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int metaslab_bias_enabled = B_TRUE;
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static uint64_t metaslab_fragmentation(metaslab_t *);
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/*
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* ==========================================================================
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* Metaslab classes
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* ==========================================================================
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*/
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metaslab_class_t *
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metaslab_class_create(spa_t *spa, metaslab_ops_t *ops)
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{
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metaslab_class_t *mc;
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mc = kmem_zalloc(sizeof (metaslab_class_t), KM_SLEEP);
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mc->mc_spa = spa;
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mc->mc_rotor = NULL;
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mc->mc_ops = ops;
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return (mc);
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}
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void
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metaslab_class_destroy(metaslab_class_t *mc)
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{
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ASSERT(mc->mc_rotor == NULL);
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ASSERT(mc->mc_alloc == 0);
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ASSERT(mc->mc_deferred == 0);
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ASSERT(mc->mc_space == 0);
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ASSERT(mc->mc_dspace == 0);
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kmem_free(mc, sizeof (metaslab_class_t));
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}
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int
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metaslab_class_validate(metaslab_class_t *mc)
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{
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metaslab_group_t *mg;
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vdev_t *vd;
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/*
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* Must hold one of the spa_config locks.
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*/
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ASSERT(spa_config_held(mc->mc_spa, SCL_ALL, RW_READER) ||
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spa_config_held(mc->mc_spa, SCL_ALL, RW_WRITER));
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if ((mg = mc->mc_rotor) == NULL)
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return (0);
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do {
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vd = mg->mg_vd;
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ASSERT(vd->vdev_mg != NULL);
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ASSERT3P(vd->vdev_top, ==, vd);
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ASSERT3P(mg->mg_class, ==, mc);
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ASSERT3P(vd->vdev_ops, !=, &vdev_hole_ops);
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} while ((mg = mg->mg_next) != mc->mc_rotor);
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return (0);
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}
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void
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metaslab_class_space_update(metaslab_class_t *mc, int64_t alloc_delta,
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int64_t defer_delta, int64_t space_delta, int64_t dspace_delta)
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{
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atomic_add_64(&mc->mc_alloc, alloc_delta);
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atomic_add_64(&mc->mc_deferred, defer_delta);
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atomic_add_64(&mc->mc_space, space_delta);
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atomic_add_64(&mc->mc_dspace, dspace_delta);
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}
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uint64_t
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metaslab_class_get_alloc(metaslab_class_t *mc)
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{
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return (mc->mc_alloc);
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}
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uint64_t
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metaslab_class_get_deferred(metaslab_class_t *mc)
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{
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return (mc->mc_deferred);
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}
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uint64_t
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metaslab_class_get_space(metaslab_class_t *mc)
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{
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return (mc->mc_space);
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}
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uint64_t
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metaslab_class_get_dspace(metaslab_class_t *mc)
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{
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return (spa_deflate(mc->mc_spa) ? mc->mc_dspace : mc->mc_space);
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}
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void
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metaslab_class_histogram_verify(metaslab_class_t *mc)
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{
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vdev_t *rvd = mc->mc_spa->spa_root_vdev;
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uint64_t *mc_hist;
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int i, c;
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if ((zfs_flags & ZFS_DEBUG_HISTOGRAM_VERIFY) == 0)
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return;
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mc_hist = kmem_zalloc(sizeof (uint64_t) * RANGE_TREE_HISTOGRAM_SIZE,
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KM_SLEEP);
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for (c = 0; c < rvd->vdev_children; c++) {
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vdev_t *tvd = rvd->vdev_child[c];
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metaslab_group_t *mg = tvd->vdev_mg;
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/*
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* Skip any holes, uninitialized top-levels, or
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* vdevs that are not in this metalab class.
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*/
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if (tvd->vdev_ishole || tvd->vdev_ms_shift == 0 ||
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mg->mg_class != mc) {
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continue;
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}
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for (i = 0; i < RANGE_TREE_HISTOGRAM_SIZE; i++)
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mc_hist[i] += mg->mg_histogram[i];
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}
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for (i = 0; i < RANGE_TREE_HISTOGRAM_SIZE; i++)
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VERIFY3U(mc_hist[i], ==, mc->mc_histogram[i]);
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kmem_free(mc_hist, sizeof (uint64_t) * RANGE_TREE_HISTOGRAM_SIZE);
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}
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/*
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* Calculate the metaslab class's fragmentation metric. The metric
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* is weighted based on the space contribution of each metaslab group.
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* The return value will be a number between 0 and 100 (inclusive), or
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* ZFS_FRAG_INVALID if the metric has not been set. See comment above the
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* zfs_frag_table for more information about the metric.
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*/
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uint64_t
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metaslab_class_fragmentation(metaslab_class_t *mc)
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{
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vdev_t *rvd = mc->mc_spa->spa_root_vdev;
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uint64_t fragmentation = 0;
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int c;
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spa_config_enter(mc->mc_spa, SCL_VDEV, FTAG, RW_READER);
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for (c = 0; c < rvd->vdev_children; c++) {
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vdev_t *tvd = rvd->vdev_child[c];
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metaslab_group_t *mg = tvd->vdev_mg;
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/*
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* Skip any holes, uninitialized top-levels, or
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* vdevs that are not in this metalab class.
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*/
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if (tvd->vdev_ishole || tvd->vdev_ms_shift == 0 ||
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mg->mg_class != mc) {
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continue;
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}
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/*
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* If a metaslab group does not contain a fragmentation
|
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* metric then just bail out.
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*/
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if (mg->mg_fragmentation == ZFS_FRAG_INVALID) {
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spa_config_exit(mc->mc_spa, SCL_VDEV, FTAG);
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return (ZFS_FRAG_INVALID);
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}
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|
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/*
|
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* Determine how much this metaslab_group is contributing
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* to the overall pool fragmentation metric.
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*/
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fragmentation += mg->mg_fragmentation *
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metaslab_group_get_space(mg);
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}
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fragmentation /= metaslab_class_get_space(mc);
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ASSERT3U(fragmentation, <=, 100);
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spa_config_exit(mc->mc_spa, SCL_VDEV, FTAG);
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return (fragmentation);
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}
|
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|
|
/*
|
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* Calculate the amount of expandable space that is available in
|
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* this metaslab class. If a device is expanded then its expandable
|
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* space will be the amount of allocatable space that is currently not
|
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* part of this metaslab class.
|
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*/
|
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uint64_t
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metaslab_class_expandable_space(metaslab_class_t *mc)
|
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{
|
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vdev_t *rvd = mc->mc_spa->spa_root_vdev;
|
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uint64_t space = 0;
|
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int c;
|
|
|
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spa_config_enter(mc->mc_spa, SCL_VDEV, FTAG, RW_READER);
|
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for (c = 0; c < rvd->vdev_children; c++) {
|
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vdev_t *tvd = rvd->vdev_child[c];
|
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metaslab_group_t *mg = tvd->vdev_mg;
|
|
|
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if (tvd->vdev_ishole || tvd->vdev_ms_shift == 0 ||
|
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mg->mg_class != mc) {
|
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continue;
|
|
}
|
|
|
|
space += tvd->vdev_max_asize - tvd->vdev_asize;
|
|
}
|
|
spa_config_exit(mc->mc_spa, SCL_VDEV, FTAG);
|
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return (space);
|
|
}
|
|
|
|
/*
|
|
* ==========================================================================
|
|
* Metaslab groups
|
|
* ==========================================================================
|
|
*/
|
|
static int
|
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metaslab_compare(const void *x1, const void *x2)
|
|
{
|
|
const metaslab_t *m1 = x1;
|
|
const metaslab_t *m2 = x2;
|
|
|
|
if (m1->ms_weight < m2->ms_weight)
|
|
return (1);
|
|
if (m1->ms_weight > m2->ms_weight)
|
|
return (-1);
|
|
|
|
/*
|
|
* If the weights are identical, use the offset to force uniqueness.
|
|
*/
|
|
if (m1->ms_start < m2->ms_start)
|
|
return (-1);
|
|
if (m1->ms_start > m2->ms_start)
|
|
return (1);
|
|
|
|
ASSERT3P(m1, ==, m2);
|
|
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Update the allocatable flag and the metaslab group's capacity.
|
|
* The allocatable flag is set to true if the capacity is below
|
|
* the zfs_mg_noalloc_threshold. If a metaslab group transitions
|
|
* from allocatable to non-allocatable or vice versa then the metaslab
|
|
* group's class is updated to reflect the transition.
|
|
*/
|
|
static void
|
|
metaslab_group_alloc_update(metaslab_group_t *mg)
|
|
{
|
|
vdev_t *vd = mg->mg_vd;
|
|
metaslab_class_t *mc = mg->mg_class;
|
|
vdev_stat_t *vs = &vd->vdev_stat;
|
|
boolean_t was_allocatable;
|
|
|
|
ASSERT(vd == vd->vdev_top);
|
|
|
|
mutex_enter(&mg->mg_lock);
|
|
was_allocatable = mg->mg_allocatable;
|
|
|
|
mg->mg_free_capacity = ((vs->vs_space - vs->vs_alloc) * 100) /
|
|
(vs->vs_space + 1);
|
|
|
|
/*
|
|
* A metaslab group is considered allocatable if it has plenty
|
|
* of free space or is not heavily fragmented. We only take
|
|
* fragmentation into account if the metaslab group has a valid
|
|
* fragmentation metric (i.e. a value between 0 and 100).
|
|
*/
|
|
mg->mg_allocatable = (mg->mg_free_capacity > zfs_mg_noalloc_threshold &&
|
|
(mg->mg_fragmentation == ZFS_FRAG_INVALID ||
|
|
mg->mg_fragmentation <= zfs_mg_fragmentation_threshold));
|
|
|
|
/*
|
|
* The mc_alloc_groups maintains a count of the number of
|
|
* groups in this metaslab class that are still above the
|
|
* zfs_mg_noalloc_threshold. This is used by the allocating
|
|
* threads to determine if they should avoid allocations to
|
|
* a given group. The allocator will avoid allocations to a group
|
|
* if that group has reached or is below the zfs_mg_noalloc_threshold
|
|
* and there are still other groups that are above the threshold.
|
|
* When a group transitions from allocatable to non-allocatable or
|
|
* vice versa we update the metaslab class to reflect that change.
|
|
* When the mc_alloc_groups value drops to 0 that means that all
|
|
* groups have reached the zfs_mg_noalloc_threshold making all groups
|
|
* eligible for allocations. This effectively means that all devices
|
|
* are balanced again.
|
|
*/
|
|
if (was_allocatable && !mg->mg_allocatable)
|
|
mc->mc_alloc_groups--;
|
|
else if (!was_allocatable && mg->mg_allocatable)
|
|
mc->mc_alloc_groups++;
|
|
|
|
mutex_exit(&mg->mg_lock);
|
|
}
|
|
|
|
metaslab_group_t *
|
|
metaslab_group_create(metaslab_class_t *mc, vdev_t *vd)
|
|
{
|
|
metaslab_group_t *mg;
|
|
|
|
mg = kmem_zalloc(sizeof (metaslab_group_t), KM_SLEEP);
|
|
mutex_init(&mg->mg_lock, NULL, MUTEX_DEFAULT, NULL);
|
|
avl_create(&mg->mg_metaslab_tree, metaslab_compare,
|
|
sizeof (metaslab_t), offsetof(struct metaslab, ms_group_node));
|
|
mg->mg_vd = vd;
|
|
mg->mg_class = mc;
|
|
mg->mg_activation_count = 0;
|
|
|
|
mg->mg_taskq = taskq_create("metaslab_group_taskq", metaslab_load_pct,
|
|
maxclsyspri, 10, INT_MAX, TASKQ_THREADS_CPU_PCT | TASKQ_DYNAMIC);
|
|
|
|
return (mg);
|
|
}
|
|
|
|
void
|
|
metaslab_group_destroy(metaslab_group_t *mg)
|
|
{
|
|
ASSERT(mg->mg_prev == NULL);
|
|
ASSERT(mg->mg_next == NULL);
|
|
/*
|
|
* We may have gone below zero with the activation count
|
|
* either because we never activated in the first place or
|
|
* because we're done, and possibly removing the vdev.
|
|
*/
|
|
ASSERT(mg->mg_activation_count <= 0);
|
|
|
|
taskq_destroy(mg->mg_taskq);
|
|
avl_destroy(&mg->mg_metaslab_tree);
|
|
mutex_destroy(&mg->mg_lock);
|
|
kmem_free(mg, sizeof (metaslab_group_t));
|
|
}
|
|
|
|
void
|
|
metaslab_group_activate(metaslab_group_t *mg)
|
|
{
|
|
metaslab_class_t *mc = mg->mg_class;
|
|
metaslab_group_t *mgprev, *mgnext;
|
|
|
|
ASSERT(spa_config_held(mc->mc_spa, SCL_ALLOC, RW_WRITER));
|
|
|
|
ASSERT(mc->mc_rotor != mg);
|
|
ASSERT(mg->mg_prev == NULL);
|
|
ASSERT(mg->mg_next == NULL);
|
|
ASSERT(mg->mg_activation_count <= 0);
|
|
|
|
if (++mg->mg_activation_count <= 0)
|
|
return;
|
|
|
|
mg->mg_aliquot = metaslab_aliquot * MAX(1, mg->mg_vd->vdev_children);
|
|
metaslab_group_alloc_update(mg);
|
|
|
|
if ((mgprev = mc->mc_rotor) == NULL) {
|
|
mg->mg_prev = mg;
|
|
mg->mg_next = mg;
|
|
} else {
|
|
mgnext = mgprev->mg_next;
|
|
mg->mg_prev = mgprev;
|
|
mg->mg_next = mgnext;
|
|
mgprev->mg_next = mg;
|
|
mgnext->mg_prev = mg;
|
|
}
|
|
mc->mc_rotor = mg;
|
|
}
|
|
|
|
void
|
|
metaslab_group_passivate(metaslab_group_t *mg)
|
|
{
|
|
metaslab_class_t *mc = mg->mg_class;
|
|
metaslab_group_t *mgprev, *mgnext;
|
|
|
|
ASSERT(spa_config_held(mc->mc_spa, SCL_ALLOC, RW_WRITER));
|
|
|
|
if (--mg->mg_activation_count != 0) {
|
|
ASSERT(mc->mc_rotor != mg);
|
|
ASSERT(mg->mg_prev == NULL);
|
|
ASSERT(mg->mg_next == NULL);
|
|
ASSERT(mg->mg_activation_count < 0);
|
|
return;
|
|
}
|
|
|
|
taskq_wait_outstanding(mg->mg_taskq, 0);
|
|
metaslab_group_alloc_update(mg);
|
|
|
|
mgprev = mg->mg_prev;
|
|
mgnext = mg->mg_next;
|
|
|
|
if (mg == mgnext) {
|
|
mc->mc_rotor = NULL;
|
|
} else {
|
|
mc->mc_rotor = mgnext;
|
|
mgprev->mg_next = mgnext;
|
|
mgnext->mg_prev = mgprev;
|
|
}
|
|
|
|
mg->mg_prev = NULL;
|
|
mg->mg_next = NULL;
|
|
}
|
|
|
|
uint64_t
|
|
metaslab_group_get_space(metaslab_group_t *mg)
|
|
{
|
|
return ((1ULL << mg->mg_vd->vdev_ms_shift) * mg->mg_vd->vdev_ms_count);
|
|
}
|
|
|
|
void
|
|
metaslab_group_histogram_verify(metaslab_group_t *mg)
|
|
{
|
|
uint64_t *mg_hist;
|
|
vdev_t *vd = mg->mg_vd;
|
|
uint64_t ashift = vd->vdev_ashift;
|
|
int i, m;
|
|
|
|
if ((zfs_flags & ZFS_DEBUG_HISTOGRAM_VERIFY) == 0)
|
|
return;
|
|
|
|
mg_hist = kmem_zalloc(sizeof (uint64_t) * RANGE_TREE_HISTOGRAM_SIZE,
|
|
KM_SLEEP);
|
|
|
|
ASSERT3U(RANGE_TREE_HISTOGRAM_SIZE, >=,
|
|
SPACE_MAP_HISTOGRAM_SIZE + ashift);
|
|
|
|
for (m = 0; m < vd->vdev_ms_count; m++) {
|
|
metaslab_t *msp = vd->vdev_ms[m];
|
|
|
|
if (msp->ms_sm == NULL)
|
|
continue;
|
|
|
|
for (i = 0; i < SPACE_MAP_HISTOGRAM_SIZE; i++)
|
|
mg_hist[i + ashift] +=
|
|
msp->ms_sm->sm_phys->smp_histogram[i];
|
|
}
|
|
|
|
for (i = 0; i < RANGE_TREE_HISTOGRAM_SIZE; i ++)
|
|
VERIFY3U(mg_hist[i], ==, mg->mg_histogram[i]);
|
|
|
|
kmem_free(mg_hist, sizeof (uint64_t) * RANGE_TREE_HISTOGRAM_SIZE);
|
|
}
|
|
|
|
static void
|
|
metaslab_group_histogram_add(metaslab_group_t *mg, metaslab_t *msp)
|
|
{
|
|
metaslab_class_t *mc = mg->mg_class;
|
|
uint64_t ashift = mg->mg_vd->vdev_ashift;
|
|
int i;
|
|
|
|
ASSERT(MUTEX_HELD(&msp->ms_lock));
|
|
if (msp->ms_sm == NULL)
|
|
return;
|
|
|
|
mutex_enter(&mg->mg_lock);
|
|
for (i = 0; i < SPACE_MAP_HISTOGRAM_SIZE; i++) {
|
|
mg->mg_histogram[i + ashift] +=
|
|
msp->ms_sm->sm_phys->smp_histogram[i];
|
|
mc->mc_histogram[i + ashift] +=
|
|
msp->ms_sm->sm_phys->smp_histogram[i];
|
|
}
|
|
mutex_exit(&mg->mg_lock);
|
|
}
|
|
|
|
void
|
|
metaslab_group_histogram_remove(metaslab_group_t *mg, metaslab_t *msp)
|
|
{
|
|
metaslab_class_t *mc = mg->mg_class;
|
|
uint64_t ashift = mg->mg_vd->vdev_ashift;
|
|
int i;
|
|
|
|
ASSERT(MUTEX_HELD(&msp->ms_lock));
|
|
if (msp->ms_sm == NULL)
|
|
return;
|
|
|
|
mutex_enter(&mg->mg_lock);
|
|
for (i = 0; i < SPACE_MAP_HISTOGRAM_SIZE; i++) {
|
|
ASSERT3U(mg->mg_histogram[i + ashift], >=,
|
|
msp->ms_sm->sm_phys->smp_histogram[i]);
|
|
ASSERT3U(mc->mc_histogram[i + ashift], >=,
|
|
msp->ms_sm->sm_phys->smp_histogram[i]);
|
|
|
|
mg->mg_histogram[i + ashift] -=
|
|
msp->ms_sm->sm_phys->smp_histogram[i];
|
|
mc->mc_histogram[i + ashift] -=
|
|
msp->ms_sm->sm_phys->smp_histogram[i];
|
|
}
|
|
mutex_exit(&mg->mg_lock);
|
|
}
|
|
|
|
static void
|
|
metaslab_group_add(metaslab_group_t *mg, metaslab_t *msp)
|
|
{
|
|
ASSERT(msp->ms_group == NULL);
|
|
mutex_enter(&mg->mg_lock);
|
|
msp->ms_group = mg;
|
|
msp->ms_weight = 0;
|
|
avl_add(&mg->mg_metaslab_tree, msp);
|
|
mutex_exit(&mg->mg_lock);
|
|
|
|
mutex_enter(&msp->ms_lock);
|
|
metaslab_group_histogram_add(mg, msp);
|
|
mutex_exit(&msp->ms_lock);
|
|
}
|
|
|
|
static void
|
|
metaslab_group_remove(metaslab_group_t *mg, metaslab_t *msp)
|
|
{
|
|
mutex_enter(&msp->ms_lock);
|
|
metaslab_group_histogram_remove(mg, msp);
|
|
mutex_exit(&msp->ms_lock);
|
|
|
|
mutex_enter(&mg->mg_lock);
|
|
ASSERT(msp->ms_group == mg);
|
|
avl_remove(&mg->mg_metaslab_tree, msp);
|
|
msp->ms_group = NULL;
|
|
mutex_exit(&mg->mg_lock);
|
|
}
|
|
|
|
static void
|
|
metaslab_group_sort(metaslab_group_t *mg, metaslab_t *msp, uint64_t weight)
|
|
{
|
|
/*
|
|
* Although in principle the weight can be any value, in
|
|
* practice we do not use values in the range [1, 511].
|
|
*/
|
|
ASSERT(weight >= SPA_MINBLOCKSIZE || weight == 0);
|
|
ASSERT(MUTEX_HELD(&msp->ms_lock));
|
|
|
|
mutex_enter(&mg->mg_lock);
|
|
ASSERT(msp->ms_group == mg);
|
|
avl_remove(&mg->mg_metaslab_tree, msp);
|
|
msp->ms_weight = weight;
|
|
avl_add(&mg->mg_metaslab_tree, msp);
|
|
mutex_exit(&mg->mg_lock);
|
|
}
|
|
|
|
/*
|
|
* Calculate the fragmentation for a given metaslab group. We can use
|
|
* a simple average here since all metaslabs within the group must have
|
|
* the same size. The return value will be a value between 0 and 100
|
|
* (inclusive), or ZFS_FRAG_INVALID if less than half of the metaslab in this
|
|
* group have a fragmentation metric.
|
|
*/
|
|
uint64_t
|
|
metaslab_group_fragmentation(metaslab_group_t *mg)
|
|
{
|
|
vdev_t *vd = mg->mg_vd;
|
|
uint64_t fragmentation = 0;
|
|
uint64_t valid_ms = 0;
|
|
int m;
|
|
|
|
for (m = 0; m < vd->vdev_ms_count; m++) {
|
|
metaslab_t *msp = vd->vdev_ms[m];
|
|
|
|
if (msp->ms_fragmentation == ZFS_FRAG_INVALID)
|
|
continue;
|
|
|
|
valid_ms++;
|
|
fragmentation += msp->ms_fragmentation;
|
|
}
|
|
|
|
if (valid_ms <= vd->vdev_ms_count / 2)
|
|
return (ZFS_FRAG_INVALID);
|
|
|
|
fragmentation /= valid_ms;
|
|
ASSERT3U(fragmentation, <=, 100);
|
|
return (fragmentation);
|
|
}
|
|
|
|
/*
|
|
* Determine if a given metaslab group should skip allocations. A metaslab
|
|
* group should avoid allocations if its free capacity is less than the
|
|
* zfs_mg_noalloc_threshold or its fragmentation metric is greater than
|
|
* zfs_mg_fragmentation_threshold and there is at least one metaslab group
|
|
* that can still handle allocations.
|
|
*/
|
|
static boolean_t
|
|
metaslab_group_allocatable(metaslab_group_t *mg)
|
|
{
|
|
vdev_t *vd = mg->mg_vd;
|
|
spa_t *spa = vd->vdev_spa;
|
|
metaslab_class_t *mc = mg->mg_class;
|
|
|
|
/*
|
|
* We use two key metrics to determine if a metaslab group is
|
|
* considered allocatable -- free space and fragmentation. If
|
|
* the free space is greater than the free space threshold and
|
|
* the fragmentation is less than the fragmentation threshold then
|
|
* consider the group allocatable. There are two case when we will
|
|
* not consider these key metrics. The first is if the group is
|
|
* associated with a slog device and the second is if all groups
|
|
* in this metaslab class have already been consider ineligible
|
|
* for allocations.
|
|
*/
|
|
return ((mg->mg_free_capacity > zfs_mg_noalloc_threshold &&
|
|
(mg->mg_fragmentation == ZFS_FRAG_INVALID ||
|
|
mg->mg_fragmentation <= zfs_mg_fragmentation_threshold)) ||
|
|
mc != spa_normal_class(spa) || mc->mc_alloc_groups == 0);
|
|
}
|
|
|
|
/*
|
|
* ==========================================================================
|
|
* Range tree callbacks
|
|
* ==========================================================================
|
|
*/
|
|
|
|
/*
|
|
* Comparison function for the private size-ordered tree. Tree is sorted
|
|
* by size, larger sizes at the end of the tree.
|
|
*/
|
|
static int
|
|
metaslab_rangesize_compare(const void *x1, const void *x2)
|
|
{
|
|
const range_seg_t *r1 = x1;
|
|
const range_seg_t *r2 = x2;
|
|
uint64_t rs_size1 = r1->rs_end - r1->rs_start;
|
|
uint64_t rs_size2 = r2->rs_end - r2->rs_start;
|
|
|
|
if (rs_size1 < rs_size2)
|
|
return (-1);
|
|
if (rs_size1 > rs_size2)
|
|
return (1);
|
|
|
|
if (r1->rs_start < r2->rs_start)
|
|
return (-1);
|
|
|
|
if (r1->rs_start > r2->rs_start)
|
|
return (1);
|
|
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Create any block allocator specific components. The current allocators
|
|
* rely on using both a size-ordered range_tree_t and an array of uint64_t's.
|
|
*/
|
|
static void
|
|
metaslab_rt_create(range_tree_t *rt, void *arg)
|
|
{
|
|
metaslab_t *msp = arg;
|
|
|
|
ASSERT3P(rt->rt_arg, ==, msp);
|
|
ASSERT(msp->ms_tree == NULL);
|
|
|
|
avl_create(&msp->ms_size_tree, metaslab_rangesize_compare,
|
|
sizeof (range_seg_t), offsetof(range_seg_t, rs_pp_node));
|
|
}
|
|
|
|
/*
|
|
* Destroy the block allocator specific components.
|
|
*/
|
|
static void
|
|
metaslab_rt_destroy(range_tree_t *rt, void *arg)
|
|
{
|
|
metaslab_t *msp = arg;
|
|
|
|
ASSERT3P(rt->rt_arg, ==, msp);
|
|
ASSERT3P(msp->ms_tree, ==, rt);
|
|
ASSERT0(avl_numnodes(&msp->ms_size_tree));
|
|
|
|
avl_destroy(&msp->ms_size_tree);
|
|
}
|
|
|
|
static void
|
|
metaslab_rt_add(range_tree_t *rt, range_seg_t *rs, void *arg)
|
|
{
|
|
metaslab_t *msp = arg;
|
|
|
|
ASSERT3P(rt->rt_arg, ==, msp);
|
|
ASSERT3P(msp->ms_tree, ==, rt);
|
|
VERIFY(!msp->ms_condensing);
|
|
avl_add(&msp->ms_size_tree, rs);
|
|
}
|
|
|
|
static void
|
|
metaslab_rt_remove(range_tree_t *rt, range_seg_t *rs, void *arg)
|
|
{
|
|
metaslab_t *msp = arg;
|
|
|
|
ASSERT3P(rt->rt_arg, ==, msp);
|
|
ASSERT3P(msp->ms_tree, ==, rt);
|
|
VERIFY(!msp->ms_condensing);
|
|
avl_remove(&msp->ms_size_tree, rs);
|
|
}
|
|
|
|
static void
|
|
metaslab_rt_vacate(range_tree_t *rt, void *arg)
|
|
{
|
|
metaslab_t *msp = arg;
|
|
|
|
ASSERT3P(rt->rt_arg, ==, msp);
|
|
ASSERT3P(msp->ms_tree, ==, rt);
|
|
|
|
/*
|
|
* Normally one would walk the tree freeing nodes along the way.
|
|
* Since the nodes are shared with the range trees we can avoid
|
|
* walking all nodes and just reinitialize the avl tree. The nodes
|
|
* will be freed by the range tree, so we don't want to free them here.
|
|
*/
|
|
avl_create(&msp->ms_size_tree, metaslab_rangesize_compare,
|
|
sizeof (range_seg_t), offsetof(range_seg_t, rs_pp_node));
|
|
}
|
|
|
|
static range_tree_ops_t metaslab_rt_ops = {
|
|
metaslab_rt_create,
|
|
metaslab_rt_destroy,
|
|
metaslab_rt_add,
|
|
metaslab_rt_remove,
|
|
metaslab_rt_vacate
|
|
};
|
|
|
|
/*
|
|
* ==========================================================================
|
|
* Metaslab block operations
|
|
* ==========================================================================
|
|
*/
|
|
|
|
/*
|
|
* Return the maximum contiguous segment within the metaslab.
|
|
*/
|
|
uint64_t
|
|
metaslab_block_maxsize(metaslab_t *msp)
|
|
{
|
|
avl_tree_t *t = &msp->ms_size_tree;
|
|
range_seg_t *rs;
|
|
|
|
if (t == NULL || (rs = avl_last(t)) == NULL)
|
|
return (0ULL);
|
|
|
|
return (rs->rs_end - rs->rs_start);
|
|
}
|
|
|
|
uint64_t
|
|
metaslab_block_alloc(metaslab_t *msp, uint64_t size)
|
|
{
|
|
uint64_t start;
|
|
range_tree_t *rt = msp->ms_tree;
|
|
|
|
VERIFY(!msp->ms_condensing);
|
|
|
|
start = msp->ms_ops->msop_alloc(msp, size);
|
|
if (start != -1ULL) {
|
|
vdev_t *vd = msp->ms_group->mg_vd;
|
|
|
|
VERIFY0(P2PHASE(start, 1ULL << vd->vdev_ashift));
|
|
VERIFY0(P2PHASE(size, 1ULL << vd->vdev_ashift));
|
|
VERIFY3U(range_tree_space(rt) - size, <=, msp->ms_size);
|
|
range_tree_remove(rt, start, size);
|
|
}
|
|
return (start);
|
|
}
|
|
|
|
/*
|
|
* ==========================================================================
|
|
* Common allocator routines
|
|
* ==========================================================================
|
|
*/
|
|
|
|
#if defined(WITH_FF_BLOCK_ALLOCATOR) || \
|
|
defined(WITH_DF_BLOCK_ALLOCATOR) || \
|
|
defined(WITH_CF_BLOCK_ALLOCATOR)
|
|
/*
|
|
* This is a helper function that can be used by the allocator to find
|
|
* a suitable block to allocate. This will search the specified AVL
|
|
* tree looking for a block that matches the specified criteria.
|
|
*/
|
|
static uint64_t
|
|
metaslab_block_picker(avl_tree_t *t, uint64_t *cursor, uint64_t size,
|
|
uint64_t align)
|
|
{
|
|
range_seg_t *rs, rsearch;
|
|
avl_index_t where;
|
|
|
|
rsearch.rs_start = *cursor;
|
|
rsearch.rs_end = *cursor + size;
|
|
|
|
rs = avl_find(t, &rsearch, &where);
|
|
if (rs == NULL)
|
|
rs = avl_nearest(t, where, AVL_AFTER);
|
|
|
|
while (rs != NULL) {
|
|
uint64_t offset = P2ROUNDUP(rs->rs_start, align);
|
|
|
|
if (offset + size <= rs->rs_end) {
|
|
*cursor = offset + size;
|
|
return (offset);
|
|
}
|
|
rs = AVL_NEXT(t, rs);
|
|
}
|
|
|
|
/*
|
|
* If we know we've searched the whole map (*cursor == 0), give up.
|
|
* Otherwise, reset the cursor to the beginning and try again.
|
|
*/
|
|
if (*cursor == 0)
|
|
return (-1ULL);
|
|
|
|
*cursor = 0;
|
|
return (metaslab_block_picker(t, cursor, size, align));
|
|
}
|
|
#endif /* WITH_FF/DF/CF_BLOCK_ALLOCATOR */
|
|
|
|
#if defined(WITH_FF_BLOCK_ALLOCATOR)
|
|
/*
|
|
* ==========================================================================
|
|
* The first-fit block allocator
|
|
* ==========================================================================
|
|
*/
|
|
static uint64_t
|
|
metaslab_ff_alloc(metaslab_t *msp, uint64_t size)
|
|
{
|
|
/*
|
|
* Find the largest power of 2 block size that evenly divides the
|
|
* requested size. This is used to try to allocate blocks with similar
|
|
* alignment from the same area of the metaslab (i.e. same cursor
|
|
* bucket) but it does not guarantee that other allocations sizes
|
|
* may exist in the same region.
|
|
*/
|
|
uint64_t align = size & -size;
|
|
uint64_t *cursor = &msp->ms_lbas[highbit64(align) - 1];
|
|
avl_tree_t *t = &msp->ms_tree->rt_root;
|
|
|
|
return (metaslab_block_picker(t, cursor, size, align));
|
|
}
|
|
|
|
static metaslab_ops_t metaslab_ff_ops = {
|
|
metaslab_ff_alloc
|
|
};
|
|
|
|
metaslab_ops_t *zfs_metaslab_ops = &metaslab_ff_ops;
|
|
#endif /* WITH_FF_BLOCK_ALLOCATOR */
|
|
|
|
#if defined(WITH_DF_BLOCK_ALLOCATOR)
|
|
/*
|
|
* ==========================================================================
|
|
* Dynamic block allocator -
|
|
* Uses the first fit allocation scheme until space get low and then
|
|
* adjusts to a best fit allocation method. Uses metaslab_df_alloc_threshold
|
|
* and metaslab_df_free_pct to determine when to switch the allocation scheme.
|
|
* ==========================================================================
|
|
*/
|
|
static uint64_t
|
|
metaslab_df_alloc(metaslab_t *msp, uint64_t size)
|
|
{
|
|
/*
|
|
* Find the largest power of 2 block size that evenly divides the
|
|
* requested size. This is used to try to allocate blocks with similar
|
|
* alignment from the same area of the metaslab (i.e. same cursor
|
|
* bucket) but it does not guarantee that other allocations sizes
|
|
* may exist in the same region.
|
|
*/
|
|
uint64_t align = size & -size;
|
|
uint64_t *cursor = &msp->ms_lbas[highbit64(align) - 1];
|
|
range_tree_t *rt = msp->ms_tree;
|
|
avl_tree_t *t = &rt->rt_root;
|
|
uint64_t max_size = metaslab_block_maxsize(msp);
|
|
int free_pct = range_tree_space(rt) * 100 / msp->ms_size;
|
|
|
|
ASSERT(MUTEX_HELD(&msp->ms_lock));
|
|
ASSERT3U(avl_numnodes(t), ==, avl_numnodes(&msp->ms_size_tree));
|
|
|
|
if (max_size < size)
|
|
return (-1ULL);
|
|
|
|
/*
|
|
* If we're running low on space switch to using the size
|
|
* sorted AVL tree (best-fit).
|
|
*/
|
|
if (max_size < metaslab_df_alloc_threshold ||
|
|
free_pct < metaslab_df_free_pct) {
|
|
t = &msp->ms_size_tree;
|
|
*cursor = 0;
|
|
}
|
|
|
|
return (metaslab_block_picker(t, cursor, size, 1ULL));
|
|
}
|
|
|
|
static metaslab_ops_t metaslab_df_ops = {
|
|
metaslab_df_alloc
|
|
};
|
|
|
|
metaslab_ops_t *zfs_metaslab_ops = &metaslab_df_ops;
|
|
#endif /* WITH_DF_BLOCK_ALLOCATOR */
|
|
|
|
#if defined(WITH_CF_BLOCK_ALLOCATOR)
|
|
/*
|
|
* ==========================================================================
|
|
* Cursor fit block allocator -
|
|
* Select the largest region in the metaslab, set the cursor to the beginning
|
|
* of the range and the cursor_end to the end of the range. As allocations
|
|
* are made advance the cursor. Continue allocating from the cursor until
|
|
* the range is exhausted and then find a new range.
|
|
* ==========================================================================
|
|
*/
|
|
static uint64_t
|
|
metaslab_cf_alloc(metaslab_t *msp, uint64_t size)
|
|
{
|
|
range_tree_t *rt = msp->ms_tree;
|
|
avl_tree_t *t = &msp->ms_size_tree;
|
|
uint64_t *cursor = &msp->ms_lbas[0];
|
|
uint64_t *cursor_end = &msp->ms_lbas[1];
|
|
uint64_t offset = 0;
|
|
|
|
ASSERT(MUTEX_HELD(&msp->ms_lock));
|
|
ASSERT3U(avl_numnodes(t), ==, avl_numnodes(&rt->rt_root));
|
|
|
|
ASSERT3U(*cursor_end, >=, *cursor);
|
|
|
|
if ((*cursor + size) > *cursor_end) {
|
|
range_seg_t *rs;
|
|
|
|
rs = avl_last(&msp->ms_size_tree);
|
|
if (rs == NULL || (rs->rs_end - rs->rs_start) < size)
|
|
return (-1ULL);
|
|
|
|
*cursor = rs->rs_start;
|
|
*cursor_end = rs->rs_end;
|
|
}
|
|
|
|
offset = *cursor;
|
|
*cursor += size;
|
|
|
|
return (offset);
|
|
}
|
|
|
|
static metaslab_ops_t metaslab_cf_ops = {
|
|
metaslab_cf_alloc
|
|
};
|
|
|
|
metaslab_ops_t *zfs_metaslab_ops = &metaslab_cf_ops;
|
|
#endif /* WITH_CF_BLOCK_ALLOCATOR */
|
|
|
|
#if defined(WITH_NDF_BLOCK_ALLOCATOR)
|
|
/*
|
|
* ==========================================================================
|
|
* New dynamic fit allocator -
|
|
* Select a region that is large enough to allocate 2^metaslab_ndf_clump_shift
|
|
* contiguous blocks. If no region is found then just use the largest segment
|
|
* that remains.
|
|
* ==========================================================================
|
|
*/
|
|
|
|
/*
|
|
* Determines desired number of contiguous blocks (2^metaslab_ndf_clump_shift)
|
|
* to request from the allocator.
|
|
*/
|
|
uint64_t metaslab_ndf_clump_shift = 4;
|
|
|
|
static uint64_t
|
|
metaslab_ndf_alloc(metaslab_t *msp, uint64_t size)
|
|
{
|
|
avl_tree_t *t = &msp->ms_tree->rt_root;
|
|
avl_index_t where;
|
|
range_seg_t *rs, rsearch;
|
|
uint64_t hbit = highbit64(size);
|
|
uint64_t *cursor = &msp->ms_lbas[hbit - 1];
|
|
uint64_t max_size = metaslab_block_maxsize(msp);
|
|
|
|
ASSERT(MUTEX_HELD(&msp->ms_lock));
|
|
ASSERT3U(avl_numnodes(t), ==, avl_numnodes(&msp->ms_size_tree));
|
|
|
|
if (max_size < size)
|
|
return (-1ULL);
|
|
|
|
rsearch.rs_start = *cursor;
|
|
rsearch.rs_end = *cursor + size;
|
|
|
|
rs = avl_find(t, &rsearch, &where);
|
|
if (rs == NULL || (rs->rs_end - rs->rs_start) < size) {
|
|
t = &msp->ms_size_tree;
|
|
|
|
rsearch.rs_start = 0;
|
|
rsearch.rs_end = MIN(max_size,
|
|
1ULL << (hbit + metaslab_ndf_clump_shift));
|
|
rs = avl_find(t, &rsearch, &where);
|
|
if (rs == NULL)
|
|
rs = avl_nearest(t, where, AVL_AFTER);
|
|
ASSERT(rs != NULL);
|
|
}
|
|
|
|
if ((rs->rs_end - rs->rs_start) >= size) {
|
|
*cursor = rs->rs_start + size;
|
|
return (rs->rs_start);
|
|
}
|
|
return (-1ULL);
|
|
}
|
|
|
|
static metaslab_ops_t metaslab_ndf_ops = {
|
|
metaslab_ndf_alloc
|
|
};
|
|
|
|
metaslab_ops_t *zfs_metaslab_ops = &metaslab_ndf_ops;
|
|
#endif /* WITH_NDF_BLOCK_ALLOCATOR */
|
|
|
|
|
|
/*
|
|
* ==========================================================================
|
|
* Metaslabs
|
|
* ==========================================================================
|
|
*/
|
|
|
|
/*
|
|
* Wait for any in-progress metaslab loads to complete.
|
|
*/
|
|
void
|
|
metaslab_load_wait(metaslab_t *msp)
|
|
{
|
|
ASSERT(MUTEX_HELD(&msp->ms_lock));
|
|
|
|
while (msp->ms_loading) {
|
|
ASSERT(!msp->ms_loaded);
|
|
cv_wait(&msp->ms_load_cv, &msp->ms_lock);
|
|
}
|
|
}
|
|
|
|
int
|
|
metaslab_load(metaslab_t *msp)
|
|
{
|
|
int error = 0;
|
|
int t;
|
|
|
|
ASSERT(MUTEX_HELD(&msp->ms_lock));
|
|
ASSERT(!msp->ms_loaded);
|
|
ASSERT(!msp->ms_loading);
|
|
|
|
msp->ms_loading = B_TRUE;
|
|
|
|
/*
|
|
* If the space map has not been allocated yet, then treat
|
|
* all the space in the metaslab as free and add it to the
|
|
* ms_tree.
|
|
*/
|
|
if (msp->ms_sm != NULL)
|
|
error = space_map_load(msp->ms_sm, msp->ms_tree, SM_FREE);
|
|
else
|
|
range_tree_add(msp->ms_tree, msp->ms_start, msp->ms_size);
|
|
|
|
msp->ms_loaded = (error == 0);
|
|
msp->ms_loading = B_FALSE;
|
|
|
|
if (msp->ms_loaded) {
|
|
for (t = 0; t < TXG_DEFER_SIZE; t++) {
|
|
range_tree_walk(msp->ms_defertree[t],
|
|
range_tree_remove, msp->ms_tree);
|
|
}
|
|
}
|
|
cv_broadcast(&msp->ms_load_cv);
|
|
return (error);
|
|
}
|
|
|
|
void
|
|
metaslab_unload(metaslab_t *msp)
|
|
{
|
|
ASSERT(MUTEX_HELD(&msp->ms_lock));
|
|
range_tree_vacate(msp->ms_tree, NULL, NULL);
|
|
msp->ms_loaded = B_FALSE;
|
|
msp->ms_weight &= ~METASLAB_ACTIVE_MASK;
|
|
}
|
|
|
|
int
|
|
metaslab_init(metaslab_group_t *mg, uint64_t id, uint64_t object, uint64_t txg,
|
|
metaslab_t **msp)
|
|
{
|
|
vdev_t *vd = mg->mg_vd;
|
|
objset_t *mos = vd->vdev_spa->spa_meta_objset;
|
|
metaslab_t *ms;
|
|
int error;
|
|
|
|
ms = kmem_zalloc(sizeof (metaslab_t), KM_SLEEP);
|
|
mutex_init(&ms->ms_lock, NULL, MUTEX_DEFAULT, NULL);
|
|
cv_init(&ms->ms_load_cv, NULL, CV_DEFAULT, NULL);
|
|
ms->ms_id = id;
|
|
ms->ms_start = id << vd->vdev_ms_shift;
|
|
ms->ms_size = 1ULL << vd->vdev_ms_shift;
|
|
|
|
/*
|
|
* We only open space map objects that already exist. All others
|
|
* will be opened when we finally allocate an object for it.
|
|
*/
|
|
if (object != 0) {
|
|
error = space_map_open(&ms->ms_sm, mos, object, ms->ms_start,
|
|
ms->ms_size, vd->vdev_ashift, &ms->ms_lock);
|
|
|
|
if (error != 0) {
|
|
kmem_free(ms, sizeof (metaslab_t));
|
|
return (error);
|
|
}
|
|
|
|
ASSERT(ms->ms_sm != NULL);
|
|
}
|
|
|
|
/*
|
|
* We create the main range tree here, but we don't create the
|
|
* alloctree and freetree until metaslab_sync_done(). This serves
|
|
* two purposes: it allows metaslab_sync_done() to detect the
|
|
* addition of new space; and for debugging, it ensures that we'd
|
|
* data fault on any attempt to use this metaslab before it's ready.
|
|
*/
|
|
ms->ms_tree = range_tree_create(&metaslab_rt_ops, ms, &ms->ms_lock);
|
|
metaslab_group_add(mg, ms);
|
|
|
|
ms->ms_fragmentation = metaslab_fragmentation(ms);
|
|
ms->ms_ops = mg->mg_class->mc_ops;
|
|
|
|
/*
|
|
* If we're opening an existing pool (txg == 0) or creating
|
|
* a new one (txg == TXG_INITIAL), all space is available now.
|
|
* If we're adding space to an existing pool, the new space
|
|
* does not become available until after this txg has synced.
|
|
*/
|
|
if (txg <= TXG_INITIAL)
|
|
metaslab_sync_done(ms, 0);
|
|
|
|
/*
|
|
* If metaslab_debug_load is set and we're initializing a metaslab
|
|
* that has an allocated space_map object then load the its space
|
|
* map so that can verify frees.
|
|
*/
|
|
if (metaslab_debug_load && ms->ms_sm != NULL) {
|
|
mutex_enter(&ms->ms_lock);
|
|
VERIFY0(metaslab_load(ms));
|
|
mutex_exit(&ms->ms_lock);
|
|
}
|
|
|
|
if (txg != 0) {
|
|
vdev_dirty(vd, 0, NULL, txg);
|
|
vdev_dirty(vd, VDD_METASLAB, ms, txg);
|
|
}
|
|
|
|
*msp = ms;
|
|
|
|
return (0);
|
|
}
|
|
|
|
void
|
|
metaslab_fini(metaslab_t *msp)
|
|
{
|
|
int t;
|
|
|
|
metaslab_group_t *mg = msp->ms_group;
|
|
|
|
metaslab_group_remove(mg, msp);
|
|
|
|
mutex_enter(&msp->ms_lock);
|
|
|
|
VERIFY(msp->ms_group == NULL);
|
|
vdev_space_update(mg->mg_vd, -space_map_allocated(msp->ms_sm),
|
|
0, -msp->ms_size);
|
|
space_map_close(msp->ms_sm);
|
|
|
|
metaslab_unload(msp);
|
|
range_tree_destroy(msp->ms_tree);
|
|
|
|
for (t = 0; t < TXG_SIZE; t++) {
|
|
range_tree_destroy(msp->ms_alloctree[t]);
|
|
range_tree_destroy(msp->ms_freetree[t]);
|
|
}
|
|
|
|
for (t = 0; t < TXG_DEFER_SIZE; t++) {
|
|
range_tree_destroy(msp->ms_defertree[t]);
|
|
}
|
|
|
|
ASSERT0(msp->ms_deferspace);
|
|
|
|
mutex_exit(&msp->ms_lock);
|
|
cv_destroy(&msp->ms_load_cv);
|
|
mutex_destroy(&msp->ms_lock);
|
|
|
|
kmem_free(msp, sizeof (metaslab_t));
|
|
}
|
|
|
|
#define FRAGMENTATION_TABLE_SIZE 17
|
|
|
|
/*
|
|
* This table defines a segment size based fragmentation metric that will
|
|
* allow each metaslab to derive its own fragmentation value. This is done
|
|
* by calculating the space in each bucket of the spacemap histogram and
|
|
* multiplying that by the fragmetation metric in this table. Doing
|
|
* this for all buckets and dividing it by the total amount of free
|
|
* space in this metaslab (i.e. the total free space in all buckets) gives
|
|
* us the fragmentation metric. This means that a high fragmentation metric
|
|
* equates to most of the free space being comprised of small segments.
|
|
* Conversely, if the metric is low, then most of the free space is in
|
|
* large segments. A 10% change in fragmentation equates to approximately
|
|
* double the number of segments.
|
|
*
|
|
* This table defines 0% fragmented space using 16MB segments. Testing has
|
|
* shown that segments that are greater than or equal to 16MB do not suffer
|
|
* from drastic performance problems. Using this value, we derive the rest
|
|
* of the table. Since the fragmentation value is never stored on disk, it
|
|
* is possible to change these calculations in the future.
|
|
*/
|
|
int zfs_frag_table[FRAGMENTATION_TABLE_SIZE] = {
|
|
100, /* 512B */
|
|
100, /* 1K */
|
|
98, /* 2K */
|
|
95, /* 4K */
|
|
90, /* 8K */
|
|
80, /* 16K */
|
|
70, /* 32K */
|
|
60, /* 64K */
|
|
50, /* 128K */
|
|
40, /* 256K */
|
|
30, /* 512K */
|
|
20, /* 1M */
|
|
15, /* 2M */
|
|
10, /* 4M */
|
|
5, /* 8M */
|
|
0 /* 16M */
|
|
};
|
|
|
|
/*
|
|
* Calclate the metaslab's fragmentation metric. A return value
|
|
* of ZFS_FRAG_INVALID means that the metaslab has not been upgraded and does
|
|
* not support this metric. Otherwise, the return value should be in the
|
|
* range [0, 100].
|
|
*/
|
|
static uint64_t
|
|
metaslab_fragmentation(metaslab_t *msp)
|
|
{
|
|
spa_t *spa = msp->ms_group->mg_vd->vdev_spa;
|
|
uint64_t fragmentation = 0;
|
|
uint64_t total = 0;
|
|
boolean_t feature_enabled = spa_feature_is_enabled(spa,
|
|
SPA_FEATURE_SPACEMAP_HISTOGRAM);
|
|
int i;
|
|
|
|
if (!feature_enabled)
|
|
return (ZFS_FRAG_INVALID);
|
|
|
|
/*
|
|
* A null space map means that the entire metaslab is free
|
|
* and thus is not fragmented.
|
|
*/
|
|
if (msp->ms_sm == NULL)
|
|
return (0);
|
|
|
|
/*
|
|
* If this metaslab's space_map has not been upgraded, flag it
|
|
* so that we upgrade next time we encounter it.
|
|
*/
|
|
if (msp->ms_sm->sm_dbuf->db_size != sizeof (space_map_phys_t)) {
|
|
vdev_t *vd = msp->ms_group->mg_vd;
|
|
|
|
if (spa_writeable(vd->vdev_spa)) {
|
|
uint64_t txg = spa_syncing_txg(spa);
|
|
|
|
msp->ms_condense_wanted = B_TRUE;
|
|
vdev_dirty(vd, VDD_METASLAB, msp, txg + 1);
|
|
spa_dbgmsg(spa, "txg %llu, requesting force condense: "
|
|
"msp %p, vd %p", txg, msp, vd);
|
|
}
|
|
return (ZFS_FRAG_INVALID);
|
|
}
|
|
|
|
for (i = 0; i < SPACE_MAP_HISTOGRAM_SIZE; i++) {
|
|
uint64_t space = 0;
|
|
uint8_t shift = msp->ms_sm->sm_shift;
|
|
int idx = MIN(shift - SPA_MINBLOCKSHIFT + i,
|
|
FRAGMENTATION_TABLE_SIZE - 1);
|
|
|
|
if (msp->ms_sm->sm_phys->smp_histogram[i] == 0)
|
|
continue;
|
|
|
|
space = msp->ms_sm->sm_phys->smp_histogram[i] << (i + shift);
|
|
total += space;
|
|
|
|
ASSERT3U(idx, <, FRAGMENTATION_TABLE_SIZE);
|
|
fragmentation += space * zfs_frag_table[idx];
|
|
}
|
|
|
|
if (total > 0)
|
|
fragmentation /= total;
|
|
ASSERT3U(fragmentation, <=, 100);
|
|
return (fragmentation);
|
|
}
|
|
|
|
/*
|
|
* Compute a weight -- a selection preference value -- for the given metaslab.
|
|
* This is based on the amount of free space, the level of fragmentation,
|
|
* the LBA range, and whether the metaslab is loaded.
|
|
*/
|
|
static uint64_t
|
|
metaslab_weight(metaslab_t *msp)
|
|
{
|
|
metaslab_group_t *mg = msp->ms_group;
|
|
vdev_t *vd = mg->mg_vd;
|
|
uint64_t weight, space;
|
|
|
|
ASSERT(MUTEX_HELD(&msp->ms_lock));
|
|
|
|
/*
|
|
* This vdev is in the process of being removed so there is nothing
|
|
* for us to do here.
|
|
*/
|
|
if (vd->vdev_removing) {
|
|
ASSERT0(space_map_allocated(msp->ms_sm));
|
|
ASSERT0(vd->vdev_ms_shift);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* The baseline weight is the metaslab's free space.
|
|
*/
|
|
space = msp->ms_size - space_map_allocated(msp->ms_sm);
|
|
|
|
msp->ms_fragmentation = metaslab_fragmentation(msp);
|
|
if (metaslab_fragmentation_factor_enabled &&
|
|
msp->ms_fragmentation != ZFS_FRAG_INVALID) {
|
|
/*
|
|
* Use the fragmentation information to inversely scale
|
|
* down the baseline weight. We need to ensure that we
|
|
* don't exclude this metaslab completely when it's 100%
|
|
* fragmented. To avoid this we reduce the fragmented value
|
|
* by 1.
|
|
*/
|
|
space = (space * (100 - (msp->ms_fragmentation - 1))) / 100;
|
|
|
|
/*
|
|
* If space < SPA_MINBLOCKSIZE, then we will not allocate from
|
|
* this metaslab again. The fragmentation metric may have
|
|
* decreased the space to something smaller than
|
|
* SPA_MINBLOCKSIZE, so reset the space to SPA_MINBLOCKSIZE
|
|
* so that we can consume any remaining space.
|
|
*/
|
|
if (space > 0 && space < SPA_MINBLOCKSIZE)
|
|
space = SPA_MINBLOCKSIZE;
|
|
}
|
|
weight = space;
|
|
|
|
/*
|
|
* Modern disks have uniform bit density and constant angular velocity.
|
|
* Therefore, the outer recording zones are faster (higher bandwidth)
|
|
* than the inner zones by the ratio of outer to inner track diameter,
|
|
* which is typically around 2:1. We account for this by assigning
|
|
* higher weight to lower metaslabs (multiplier ranging from 2x to 1x).
|
|
* In effect, this means that we'll select the metaslab with the most
|
|
* free bandwidth rather than simply the one with the most free space.
|
|
*/
|
|
if (!vd->vdev_nonrot && metaslab_lba_weighting_enabled) {
|
|
weight = 2 * weight - (msp->ms_id * weight) / vd->vdev_ms_count;
|
|
ASSERT(weight >= space && weight <= 2 * space);
|
|
}
|
|
|
|
/*
|
|
* If this metaslab is one we're actively using, adjust its
|
|
* weight to make it preferable to any inactive metaslab so
|
|
* we'll polish it off. If the fragmentation on this metaslab
|
|
* has exceed our threshold, then don't mark it active.
|
|
*/
|
|
if (msp->ms_loaded && msp->ms_fragmentation != ZFS_FRAG_INVALID &&
|
|
msp->ms_fragmentation <= zfs_metaslab_fragmentation_threshold) {
|
|
weight |= (msp->ms_weight & METASLAB_ACTIVE_MASK);
|
|
}
|
|
|
|
return (weight);
|
|
}
|
|
|
|
static int
|
|
metaslab_activate(metaslab_t *msp, uint64_t activation_weight)
|
|
{
|
|
ASSERT(MUTEX_HELD(&msp->ms_lock));
|
|
|
|
if ((msp->ms_weight & METASLAB_ACTIVE_MASK) == 0) {
|
|
metaslab_load_wait(msp);
|
|
if (!msp->ms_loaded) {
|
|
int error = metaslab_load(msp);
|
|
if (error) {
|
|
metaslab_group_sort(msp->ms_group, msp, 0);
|
|
return (error);
|
|
}
|
|
}
|
|
|
|
metaslab_group_sort(msp->ms_group, msp,
|
|
msp->ms_weight | activation_weight);
|
|
}
|
|
ASSERT(msp->ms_loaded);
|
|
ASSERT(msp->ms_weight & METASLAB_ACTIVE_MASK);
|
|
|
|
return (0);
|
|
}
|
|
|
|
static void
|
|
metaslab_passivate(metaslab_t *msp, uint64_t size)
|
|
{
|
|
/*
|
|
* If size < SPA_MINBLOCKSIZE, then we will not allocate from
|
|
* this metaslab again. In that case, it had better be empty,
|
|
* or we would be leaving space on the table.
|
|
*/
|
|
ASSERT(size >= SPA_MINBLOCKSIZE || range_tree_space(msp->ms_tree) == 0);
|
|
metaslab_group_sort(msp->ms_group, msp, MIN(msp->ms_weight, size));
|
|
ASSERT((msp->ms_weight & METASLAB_ACTIVE_MASK) == 0);
|
|
}
|
|
|
|
static void
|
|
metaslab_preload(void *arg)
|
|
{
|
|
metaslab_t *msp = arg;
|
|
spa_t *spa = msp->ms_group->mg_vd->vdev_spa;
|
|
fstrans_cookie_t cookie = spl_fstrans_mark();
|
|
|
|
ASSERT(!MUTEX_HELD(&msp->ms_group->mg_lock));
|
|
|
|
mutex_enter(&msp->ms_lock);
|
|
metaslab_load_wait(msp);
|
|
if (!msp->ms_loaded)
|
|
(void) metaslab_load(msp);
|
|
|
|
/*
|
|
* Set the ms_access_txg value so that we don't unload it right away.
|
|
*/
|
|
msp->ms_access_txg = spa_syncing_txg(spa) + metaslab_unload_delay + 1;
|
|
mutex_exit(&msp->ms_lock);
|
|
spl_fstrans_unmark(cookie);
|
|
}
|
|
|
|
static void
|
|
metaslab_group_preload(metaslab_group_t *mg)
|
|
{
|
|
spa_t *spa = mg->mg_vd->vdev_spa;
|
|
metaslab_t *msp;
|
|
avl_tree_t *t = &mg->mg_metaslab_tree;
|
|
int m = 0;
|
|
|
|
if (spa_shutting_down(spa) || !metaslab_preload_enabled) {
|
|
taskq_wait_outstanding(mg->mg_taskq, 0);
|
|
return;
|
|
}
|
|
|
|
mutex_enter(&mg->mg_lock);
|
|
/*
|
|
* Load the next potential metaslabs
|
|
*/
|
|
msp = avl_first(t);
|
|
while (msp != NULL) {
|
|
metaslab_t *msp_next = AVL_NEXT(t, msp);
|
|
|
|
/*
|
|
* We preload only the maximum number of metaslabs specified
|
|
* by metaslab_preload_limit. If a metaslab is being forced
|
|
* to condense then we preload it too. This will ensure
|
|
* that force condensing happens in the next txg.
|
|
*/
|
|
if (++m > metaslab_preload_limit && !msp->ms_condense_wanted) {
|
|
msp = msp_next;
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* We must drop the metaslab group lock here to preserve
|
|
* lock ordering with the ms_lock (when grabbing both
|
|
* the mg_lock and the ms_lock, the ms_lock must be taken
|
|
* first). As a result, it is possible that the ordering
|
|
* of the metaslabs within the avl tree may change before
|
|
* we reacquire the lock. The metaslab cannot be removed from
|
|
* the tree while we're in syncing context so it is safe to
|
|
* drop the mg_lock here. If the metaslabs are reordered
|
|
* nothing will break -- we just may end up loading a
|
|
* less than optimal one.
|
|
*/
|
|
mutex_exit(&mg->mg_lock);
|
|
VERIFY(taskq_dispatch(mg->mg_taskq, metaslab_preload,
|
|
msp, TQ_SLEEP) != 0);
|
|
mutex_enter(&mg->mg_lock);
|
|
msp = msp_next;
|
|
}
|
|
mutex_exit(&mg->mg_lock);
|
|
}
|
|
|
|
/*
|
|
* Determine if the space map's on-disk footprint is past our tolerance
|
|
* for inefficiency. We would like to use the following criteria to make
|
|
* our decision:
|
|
*
|
|
* 1. The size of the space map object should not dramatically increase as a
|
|
* result of writing out the free space range tree.
|
|
*
|
|
* 2. The minimal on-disk space map representation is zfs_condense_pct/100
|
|
* times the size than the free space range tree representation
|
|
* (i.e. zfs_condense_pct = 110 and in-core = 1MB, minimal = 1.1.MB).
|
|
*
|
|
* 3. The on-disk size of the space map should actually decrease.
|
|
*
|
|
* Checking the first condition is tricky since we don't want to walk
|
|
* the entire AVL tree calculating the estimated on-disk size. Instead we
|
|
* use the size-ordered range tree in the metaslab and calculate the
|
|
* size required to write out the largest segment in our free tree. If the
|
|
* size required to represent that segment on disk is larger than the space
|
|
* map object then we avoid condensing this map.
|
|
*
|
|
* To determine the second criterion we use a best-case estimate and assume
|
|
* each segment can be represented on-disk as a single 64-bit entry. We refer
|
|
* to this best-case estimate as the space map's minimal form.
|
|
*
|
|
* Unfortunately, we cannot compute the on-disk size of the space map in this
|
|
* context because we cannot accurately compute the effects of compression, etc.
|
|
* Instead, we apply the heuristic described in the block comment for
|
|
* zfs_metaslab_condense_block_threshold - we only condense if the space used
|
|
* is greater than a threshold number of blocks.
|
|
*/
|
|
static boolean_t
|
|
metaslab_should_condense(metaslab_t *msp)
|
|
{
|
|
space_map_t *sm = msp->ms_sm;
|
|
range_seg_t *rs;
|
|
uint64_t size, entries, segsz, object_size, optimal_size, record_size;
|
|
dmu_object_info_t doi;
|
|
uint64_t vdev_blocksize = 1 << msp->ms_group->mg_vd->vdev_ashift;
|
|
|
|
ASSERT(MUTEX_HELD(&msp->ms_lock));
|
|
ASSERT(msp->ms_loaded);
|
|
|
|
/*
|
|
* Use the ms_size_tree range tree, which is ordered by size, to
|
|
* obtain the largest segment in the free tree. We always condense
|
|
* metaslabs that are empty and metaslabs for which a condense
|
|
* request has been made.
|
|
*/
|
|
rs = avl_last(&msp->ms_size_tree);
|
|
if (rs == NULL || msp->ms_condense_wanted)
|
|
return (B_TRUE);
|
|
|
|
/*
|
|
* Calculate the number of 64-bit entries this segment would
|
|
* require when written to disk. If this single segment would be
|
|
* larger on-disk than the entire current on-disk structure, then
|
|
* clearly condensing will increase the on-disk structure size.
|
|
*/
|
|
size = (rs->rs_end - rs->rs_start) >> sm->sm_shift;
|
|
entries = size / (MIN(size, SM_RUN_MAX));
|
|
segsz = entries * sizeof (uint64_t);
|
|
|
|
optimal_size = sizeof (uint64_t) * avl_numnodes(&msp->ms_tree->rt_root);
|
|
object_size = space_map_length(msp->ms_sm);
|
|
|
|
dmu_object_info_from_db(sm->sm_dbuf, &doi);
|
|
record_size = MAX(doi.doi_data_block_size, vdev_blocksize);
|
|
|
|
return (segsz <= object_size &&
|
|
object_size >= (optimal_size * zfs_condense_pct / 100) &&
|
|
object_size > zfs_metaslab_condense_block_threshold * record_size);
|
|
}
|
|
|
|
/*
|
|
* Condense the on-disk space map representation to its minimized form.
|
|
* The minimized form consists of a small number of allocations followed by
|
|
* the entries of the free range tree.
|
|
*/
|
|
static void
|
|
metaslab_condense(metaslab_t *msp, uint64_t txg, dmu_tx_t *tx)
|
|
{
|
|
spa_t *spa = msp->ms_group->mg_vd->vdev_spa;
|
|
range_tree_t *freetree = msp->ms_freetree[txg & TXG_MASK];
|
|
range_tree_t *condense_tree;
|
|
space_map_t *sm = msp->ms_sm;
|
|
int t;
|
|
|
|
ASSERT(MUTEX_HELD(&msp->ms_lock));
|
|
ASSERT3U(spa_sync_pass(spa), ==, 1);
|
|
ASSERT(msp->ms_loaded);
|
|
|
|
|
|
spa_dbgmsg(spa, "condensing: txg %llu, msp[%llu] %p, vdev id %llu, "
|
|
"spa %s, smp size %llu, segments %lu, forcing condense=%s", txg,
|
|
msp->ms_id, msp, msp->ms_group->mg_vd->vdev_id,
|
|
msp->ms_group->mg_vd->vdev_spa->spa_name,
|
|
space_map_length(msp->ms_sm), avl_numnodes(&msp->ms_tree->rt_root),
|
|
msp->ms_condense_wanted ? "TRUE" : "FALSE");
|
|
|
|
msp->ms_condense_wanted = B_FALSE;
|
|
|
|
/*
|
|
* Create an range tree that is 100% allocated. We remove segments
|
|
* that have been freed in this txg, any deferred frees that exist,
|
|
* and any allocation in the future. Removing segments should be
|
|
* a relatively inexpensive operation since we expect these trees to
|
|
* have a small number of nodes.
|
|
*/
|
|
condense_tree = range_tree_create(NULL, NULL, &msp->ms_lock);
|
|
range_tree_add(condense_tree, msp->ms_start, msp->ms_size);
|
|
|
|
/*
|
|
* Remove what's been freed in this txg from the condense_tree.
|
|
* Since we're in sync_pass 1, we know that all the frees from
|
|
* this txg are in the freetree.
|
|
*/
|
|
range_tree_walk(freetree, range_tree_remove, condense_tree);
|
|
|
|
for (t = 0; t < TXG_DEFER_SIZE; t++) {
|
|
range_tree_walk(msp->ms_defertree[t],
|
|
range_tree_remove, condense_tree);
|
|
}
|
|
|
|
for (t = 1; t < TXG_CONCURRENT_STATES; t++) {
|
|
range_tree_walk(msp->ms_alloctree[(txg + t) & TXG_MASK],
|
|
range_tree_remove, condense_tree);
|
|
}
|
|
|
|
/*
|
|
* We're about to drop the metaslab's lock thus allowing
|
|
* other consumers to change it's content. Set the
|
|
* metaslab's ms_condensing flag to ensure that
|
|
* allocations on this metaslab do not occur while we're
|
|
* in the middle of committing it to disk. This is only critical
|
|
* for the ms_tree as all other range trees use per txg
|
|
* views of their content.
|
|
*/
|
|
msp->ms_condensing = B_TRUE;
|
|
|
|
mutex_exit(&msp->ms_lock);
|
|
space_map_truncate(sm, tx);
|
|
mutex_enter(&msp->ms_lock);
|
|
|
|
/*
|
|
* While we would ideally like to create a space_map representation
|
|
* that consists only of allocation records, doing so can be
|
|
* prohibitively expensive because the in-core free tree can be
|
|
* large, and therefore computationally expensive to subtract
|
|
* from the condense_tree. Instead we sync out two trees, a cheap
|
|
* allocation only tree followed by the in-core free tree. While not
|
|
* optimal, this is typically close to optimal, and much cheaper to
|
|
* compute.
|
|
*/
|
|
space_map_write(sm, condense_tree, SM_ALLOC, tx);
|
|
range_tree_vacate(condense_tree, NULL, NULL);
|
|
range_tree_destroy(condense_tree);
|
|
|
|
space_map_write(sm, msp->ms_tree, SM_FREE, tx);
|
|
msp->ms_condensing = B_FALSE;
|
|
}
|
|
|
|
/*
|
|
* Write a metaslab to disk in the context of the specified transaction group.
|
|
*/
|
|
void
|
|
metaslab_sync(metaslab_t *msp, uint64_t txg)
|
|
{
|
|
metaslab_group_t *mg = msp->ms_group;
|
|
vdev_t *vd = mg->mg_vd;
|
|
spa_t *spa = vd->vdev_spa;
|
|
objset_t *mos = spa_meta_objset(spa);
|
|
range_tree_t *alloctree = msp->ms_alloctree[txg & TXG_MASK];
|
|
range_tree_t **freetree = &msp->ms_freetree[txg & TXG_MASK];
|
|
range_tree_t **freed_tree =
|
|
&msp->ms_freetree[TXG_CLEAN(txg) & TXG_MASK];
|
|
dmu_tx_t *tx;
|
|
uint64_t object = space_map_object(msp->ms_sm);
|
|
|
|
ASSERT(!vd->vdev_ishole);
|
|
|
|
/*
|
|
* This metaslab has just been added so there's no work to do now.
|
|
*/
|
|
if (*freetree == NULL) {
|
|
ASSERT3P(alloctree, ==, NULL);
|
|
return;
|
|
}
|
|
|
|
ASSERT3P(alloctree, !=, NULL);
|
|
ASSERT3P(*freetree, !=, NULL);
|
|
ASSERT3P(*freed_tree, !=, NULL);
|
|
|
|
/*
|
|
* Normally, we don't want to process a metaslab if there
|
|
* are no allocations or frees to perform. However, if the metaslab
|
|
* is being forced to condense we need to let it through.
|
|
*/
|
|
if (range_tree_space(alloctree) == 0 &&
|
|
range_tree_space(*freetree) == 0 &&
|
|
!msp->ms_condense_wanted)
|
|
return;
|
|
|
|
/*
|
|
* The only state that can actually be changing concurrently with
|
|
* metaslab_sync() is the metaslab's ms_tree. No other thread can
|
|
* be modifying this txg's alloctree, freetree, freed_tree, or
|
|
* space_map_phys_t. Therefore, we only hold ms_lock to satify
|
|
* space_map ASSERTs. We drop it whenever we call into the DMU,
|
|
* because the DMU can call down to us (e.g. via zio_free()) at
|
|
* any time.
|
|
*/
|
|
|
|
tx = dmu_tx_create_assigned(spa_get_dsl(spa), txg);
|
|
|
|
if (msp->ms_sm == NULL) {
|
|
uint64_t new_object;
|
|
|
|
new_object = space_map_alloc(mos, tx);
|
|
VERIFY3U(new_object, !=, 0);
|
|
|
|
VERIFY0(space_map_open(&msp->ms_sm, mos, new_object,
|
|
msp->ms_start, msp->ms_size, vd->vdev_ashift,
|
|
&msp->ms_lock));
|
|
ASSERT(msp->ms_sm != NULL);
|
|
}
|
|
|
|
mutex_enter(&msp->ms_lock);
|
|
|
|
/*
|
|
* Note: metaslab_condense() clears the space_map's histogram.
|
|
* Therefore we muse verify and remove this histogram before
|
|
* condensing.
|
|
*/
|
|
metaslab_group_histogram_verify(mg);
|
|
metaslab_class_histogram_verify(mg->mg_class);
|
|
metaslab_group_histogram_remove(mg, msp);
|
|
|
|
if (msp->ms_loaded && spa_sync_pass(spa) == 1 &&
|
|
metaslab_should_condense(msp)) {
|
|
metaslab_condense(msp, txg, tx);
|
|
} else {
|
|
space_map_write(msp->ms_sm, alloctree, SM_ALLOC, tx);
|
|
space_map_write(msp->ms_sm, *freetree, SM_FREE, tx);
|
|
}
|
|
|
|
if (msp->ms_loaded) {
|
|
/*
|
|
* When the space map is loaded, we have an accruate
|
|
* histogram in the range tree. This gives us an opportunity
|
|
* to bring the space map's histogram up-to-date so we clear
|
|
* it first before updating it.
|
|
*/
|
|
space_map_histogram_clear(msp->ms_sm);
|
|
space_map_histogram_add(msp->ms_sm, msp->ms_tree, tx);
|
|
} else {
|
|
/*
|
|
* Since the space map is not loaded we simply update the
|
|
* exisiting histogram with what was freed in this txg. This
|
|
* means that the on-disk histogram may not have an accurate
|
|
* view of the free space but it's close enough to allow
|
|
* us to make allocation decisions.
|
|
*/
|
|
space_map_histogram_add(msp->ms_sm, *freetree, tx);
|
|
}
|
|
metaslab_group_histogram_add(mg, msp);
|
|
metaslab_group_histogram_verify(mg);
|
|
metaslab_class_histogram_verify(mg->mg_class);
|
|
|
|
/*
|
|
* For sync pass 1, we avoid traversing this txg's free range tree
|
|
* and instead will just swap the pointers for freetree and
|
|
* freed_tree. We can safely do this since the freed_tree is
|
|
* guaranteed to be empty on the initial pass.
|
|
*/
|
|
if (spa_sync_pass(spa) == 1) {
|
|
range_tree_swap(freetree, freed_tree);
|
|
} else {
|
|
range_tree_vacate(*freetree, range_tree_add, *freed_tree);
|
|
}
|
|
range_tree_vacate(alloctree, NULL, NULL);
|
|
|
|
ASSERT0(range_tree_space(msp->ms_alloctree[txg & TXG_MASK]));
|
|
ASSERT0(range_tree_space(msp->ms_freetree[txg & TXG_MASK]));
|
|
|
|
mutex_exit(&msp->ms_lock);
|
|
|
|
if (object != space_map_object(msp->ms_sm)) {
|
|
object = space_map_object(msp->ms_sm);
|
|
dmu_write(mos, vd->vdev_ms_array, sizeof (uint64_t) *
|
|
msp->ms_id, sizeof (uint64_t), &object, tx);
|
|
}
|
|
dmu_tx_commit(tx);
|
|
}
|
|
|
|
/*
|
|
* Called after a transaction group has completely synced to mark
|
|
* all of the metaslab's free space as usable.
|
|
*/
|
|
void
|
|
metaslab_sync_done(metaslab_t *msp, uint64_t txg)
|
|
{
|
|
metaslab_group_t *mg = msp->ms_group;
|
|
vdev_t *vd = mg->mg_vd;
|
|
range_tree_t **freed_tree;
|
|
range_tree_t **defer_tree;
|
|
int64_t alloc_delta, defer_delta;
|
|
int t;
|
|
|
|
ASSERT(!vd->vdev_ishole);
|
|
|
|
mutex_enter(&msp->ms_lock);
|
|
|
|
/*
|
|
* If this metaslab is just becoming available, initialize its
|
|
* alloctrees, freetrees, and defertree and add its capacity to
|
|
* the vdev.
|
|
*/
|
|
if (msp->ms_freetree[TXG_CLEAN(txg) & TXG_MASK] == NULL) {
|
|
for (t = 0; t < TXG_SIZE; t++) {
|
|
ASSERT(msp->ms_alloctree[t] == NULL);
|
|
ASSERT(msp->ms_freetree[t] == NULL);
|
|
|
|
msp->ms_alloctree[t] = range_tree_create(NULL, msp,
|
|
&msp->ms_lock);
|
|
msp->ms_freetree[t] = range_tree_create(NULL, msp,
|
|
&msp->ms_lock);
|
|
}
|
|
|
|
for (t = 0; t < TXG_DEFER_SIZE; t++) {
|
|
ASSERT(msp->ms_defertree[t] == NULL);
|
|
|
|
msp->ms_defertree[t] = range_tree_create(NULL, msp,
|
|
&msp->ms_lock);
|
|
}
|
|
|
|
vdev_space_update(vd, 0, 0, msp->ms_size);
|
|
}
|
|
|
|
freed_tree = &msp->ms_freetree[TXG_CLEAN(txg) & TXG_MASK];
|
|
defer_tree = &msp->ms_defertree[txg % TXG_DEFER_SIZE];
|
|
|
|
alloc_delta = space_map_alloc_delta(msp->ms_sm);
|
|
defer_delta = range_tree_space(*freed_tree) -
|
|
range_tree_space(*defer_tree);
|
|
|
|
vdev_space_update(vd, alloc_delta + defer_delta, defer_delta, 0);
|
|
|
|
ASSERT0(range_tree_space(msp->ms_alloctree[txg & TXG_MASK]));
|
|
ASSERT0(range_tree_space(msp->ms_freetree[txg & TXG_MASK]));
|
|
|
|
/*
|
|
* If there's a metaslab_load() in progress, wait for it to complete
|
|
* so that we have a consistent view of the in-core space map.
|
|
*/
|
|
metaslab_load_wait(msp);
|
|
|
|
/*
|
|
* Move the frees from the defer_tree back to the free
|
|
* range tree (if it's loaded). Swap the freed_tree and the
|
|
* defer_tree -- this is safe to do because we've just emptied out
|
|
* the defer_tree.
|
|
*/
|
|
range_tree_vacate(*defer_tree,
|
|
msp->ms_loaded ? range_tree_add : NULL, msp->ms_tree);
|
|
range_tree_swap(freed_tree, defer_tree);
|
|
|
|
space_map_update(msp->ms_sm);
|
|
|
|
msp->ms_deferspace += defer_delta;
|
|
ASSERT3S(msp->ms_deferspace, >=, 0);
|
|
ASSERT3S(msp->ms_deferspace, <=, msp->ms_size);
|
|
if (msp->ms_deferspace != 0) {
|
|
/*
|
|
* Keep syncing this metaslab until all deferred frees
|
|
* are back in circulation.
|
|
*/
|
|
vdev_dirty(vd, VDD_METASLAB, msp, txg + 1);
|
|
}
|
|
|
|
if (msp->ms_loaded && msp->ms_access_txg < txg) {
|
|
for (t = 1; t < TXG_CONCURRENT_STATES; t++) {
|
|
VERIFY0(range_tree_space(
|
|
msp->ms_alloctree[(txg + t) & TXG_MASK]));
|
|
}
|
|
|
|
if (!metaslab_debug_unload)
|
|
metaslab_unload(msp);
|
|
}
|
|
|
|
metaslab_group_sort(mg, msp, metaslab_weight(msp));
|
|
mutex_exit(&msp->ms_lock);
|
|
}
|
|
|
|
void
|
|
metaslab_sync_reassess(metaslab_group_t *mg)
|
|
{
|
|
metaslab_group_alloc_update(mg);
|
|
mg->mg_fragmentation = metaslab_group_fragmentation(mg);
|
|
|
|
/*
|
|
* Preload the next potential metaslabs
|
|
*/
|
|
metaslab_group_preload(mg);
|
|
}
|
|
|
|
static uint64_t
|
|
metaslab_distance(metaslab_t *msp, dva_t *dva)
|
|
{
|
|
uint64_t ms_shift = msp->ms_group->mg_vd->vdev_ms_shift;
|
|
uint64_t offset = DVA_GET_OFFSET(dva) >> ms_shift;
|
|
uint64_t start = msp->ms_id;
|
|
|
|
if (msp->ms_group->mg_vd->vdev_id != DVA_GET_VDEV(dva))
|
|
return (1ULL << 63);
|
|
|
|
if (offset < start)
|
|
return ((start - offset) << ms_shift);
|
|
if (offset > start)
|
|
return ((offset - start) << ms_shift);
|
|
return (0);
|
|
}
|
|
|
|
static uint64_t
|
|
metaslab_group_alloc(metaslab_group_t *mg, uint64_t psize, uint64_t asize,
|
|
uint64_t txg, uint64_t min_distance, dva_t *dva, int d)
|
|
{
|
|
spa_t *spa = mg->mg_vd->vdev_spa;
|
|
metaslab_t *msp = NULL;
|
|
uint64_t offset = -1ULL;
|
|
avl_tree_t *t = &mg->mg_metaslab_tree;
|
|
uint64_t activation_weight;
|
|
uint64_t target_distance;
|
|
int i;
|
|
|
|
activation_weight = METASLAB_WEIGHT_PRIMARY;
|
|
for (i = 0; i < d; i++) {
|
|
if (DVA_GET_VDEV(&dva[i]) == mg->mg_vd->vdev_id) {
|
|
activation_weight = METASLAB_WEIGHT_SECONDARY;
|
|
break;
|
|
}
|
|
}
|
|
|
|
for (;;) {
|
|
boolean_t was_active;
|
|
|
|
mutex_enter(&mg->mg_lock);
|
|
for (msp = avl_first(t); msp; msp = AVL_NEXT(t, msp)) {
|
|
if (msp->ms_weight < asize) {
|
|
spa_dbgmsg(spa, "%s: failed to meet weight "
|
|
"requirement: vdev %llu, txg %llu, mg %p, "
|
|
"msp %p, psize %llu, asize %llu, "
|
|
"weight %llu", spa_name(spa),
|
|
mg->mg_vd->vdev_id, txg,
|
|
mg, msp, psize, asize, msp->ms_weight);
|
|
mutex_exit(&mg->mg_lock);
|
|
return (-1ULL);
|
|
}
|
|
|
|
/*
|
|
* If the selected metaslab is condensing, skip it.
|
|
*/
|
|
if (msp->ms_condensing)
|
|
continue;
|
|
|
|
was_active = msp->ms_weight & METASLAB_ACTIVE_MASK;
|
|
if (activation_weight == METASLAB_WEIGHT_PRIMARY)
|
|
break;
|
|
|
|
target_distance = min_distance +
|
|
(space_map_allocated(msp->ms_sm) != 0 ? 0 :
|
|
min_distance >> 1);
|
|
|
|
for (i = 0; i < d; i++)
|
|
if (metaslab_distance(msp, &dva[i]) <
|
|
target_distance)
|
|
break;
|
|
if (i == d)
|
|
break;
|
|
}
|
|
mutex_exit(&mg->mg_lock);
|
|
if (msp == NULL)
|
|
return (-1ULL);
|
|
|
|
mutex_enter(&msp->ms_lock);
|
|
|
|
/*
|
|
* Ensure that the metaslab we have selected is still
|
|
* capable of handling our request. It's possible that
|
|
* another thread may have changed the weight while we
|
|
* were blocked on the metaslab lock.
|
|
*/
|
|
if (msp->ms_weight < asize || (was_active &&
|
|
!(msp->ms_weight & METASLAB_ACTIVE_MASK) &&
|
|
activation_weight == METASLAB_WEIGHT_PRIMARY)) {
|
|
mutex_exit(&msp->ms_lock);
|
|
continue;
|
|
}
|
|
|
|
if ((msp->ms_weight & METASLAB_WEIGHT_SECONDARY) &&
|
|
activation_weight == METASLAB_WEIGHT_PRIMARY) {
|
|
metaslab_passivate(msp,
|
|
msp->ms_weight & ~METASLAB_ACTIVE_MASK);
|
|
mutex_exit(&msp->ms_lock);
|
|
continue;
|
|
}
|
|
|
|
if (metaslab_activate(msp, activation_weight) != 0) {
|
|
mutex_exit(&msp->ms_lock);
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* If this metaslab is currently condensing then pick again as
|
|
* we can't manipulate this metaslab until it's committed
|
|
* to disk.
|
|
*/
|
|
if (msp->ms_condensing) {
|
|
mutex_exit(&msp->ms_lock);
|
|
continue;
|
|
}
|
|
|
|
if ((offset = metaslab_block_alloc(msp, asize)) != -1ULL)
|
|
break;
|
|
|
|
metaslab_passivate(msp, metaslab_block_maxsize(msp));
|
|
mutex_exit(&msp->ms_lock);
|
|
}
|
|
|
|
if (range_tree_space(msp->ms_alloctree[txg & TXG_MASK]) == 0)
|
|
vdev_dirty(mg->mg_vd, VDD_METASLAB, msp, txg);
|
|
|
|
range_tree_add(msp->ms_alloctree[txg & TXG_MASK], offset, asize);
|
|
msp->ms_access_txg = txg + metaslab_unload_delay;
|
|
|
|
mutex_exit(&msp->ms_lock);
|
|
|
|
return (offset);
|
|
}
|
|
|
|
/*
|
|
* Allocate a block for the specified i/o.
|
|
*/
|
|
static int
|
|
metaslab_alloc_dva(spa_t *spa, metaslab_class_t *mc, uint64_t psize,
|
|
dva_t *dva, int d, dva_t *hintdva, uint64_t txg, int flags)
|
|
{
|
|
metaslab_group_t *mg, *fast_mg, *rotor;
|
|
vdev_t *vd;
|
|
int dshift = 3;
|
|
int all_zero;
|
|
int zio_lock = B_FALSE;
|
|
boolean_t allocatable;
|
|
uint64_t offset = -1ULL;
|
|
uint64_t asize;
|
|
uint64_t distance;
|
|
|
|
ASSERT(!DVA_IS_VALID(&dva[d]));
|
|
|
|
/*
|
|
* For testing, make some blocks above a certain size be gang blocks.
|
|
*/
|
|
if (psize >= metaslab_gang_bang && (ddi_get_lbolt() & 3) == 0)
|
|
return (SET_ERROR(ENOSPC));
|
|
|
|
/*
|
|
* Start at the rotor and loop through all mgs until we find something.
|
|
* Note that there's no locking on mc_rotor or mc_aliquot because
|
|
* nothing actually breaks if we miss a few updates -- we just won't
|
|
* allocate quite as evenly. It all balances out over time.
|
|
*
|
|
* If we are doing ditto or log blocks, try to spread them across
|
|
* consecutive vdevs. If we're forced to reuse a vdev before we've
|
|
* allocated all of our ditto blocks, then try and spread them out on
|
|
* that vdev as much as possible. If it turns out to not be possible,
|
|
* gradually lower our standards until anything becomes acceptable.
|
|
* Also, allocating on consecutive vdevs (as opposed to random vdevs)
|
|
* gives us hope of containing our fault domains to something we're
|
|
* able to reason about. Otherwise, any two top-level vdev failures
|
|
* will guarantee the loss of data. With consecutive allocation,
|
|
* only two adjacent top-level vdev failures will result in data loss.
|
|
*
|
|
* If we are doing gang blocks (hintdva is non-NULL), try to keep
|
|
* ourselves on the same vdev as our gang block header. That
|
|
* way, we can hope for locality in vdev_cache, plus it makes our
|
|
* fault domains something tractable.
|
|
*/
|
|
if (hintdva) {
|
|
vd = vdev_lookup_top(spa, DVA_GET_VDEV(&hintdva[d]));
|
|
|
|
/*
|
|
* It's possible the vdev we're using as the hint no
|
|
* longer exists (i.e. removed). Consult the rotor when
|
|
* all else fails.
|
|
*/
|
|
if (vd != NULL) {
|
|
mg = vd->vdev_mg;
|
|
|
|
if (flags & METASLAB_HINTBP_AVOID &&
|
|
mg->mg_next != NULL)
|
|
mg = mg->mg_next;
|
|
} else {
|
|
mg = mc->mc_rotor;
|
|
}
|
|
} else if (d != 0) {
|
|
vd = vdev_lookup_top(spa, DVA_GET_VDEV(&dva[d - 1]));
|
|
mg = vd->vdev_mg->mg_next;
|
|
} else if (flags & METASLAB_FASTWRITE) {
|
|
mg = fast_mg = mc->mc_rotor;
|
|
|
|
do {
|
|
if (fast_mg->mg_vd->vdev_pending_fastwrite <
|
|
mg->mg_vd->vdev_pending_fastwrite)
|
|
mg = fast_mg;
|
|
} while ((fast_mg = fast_mg->mg_next) != mc->mc_rotor);
|
|
|
|
} else {
|
|
mg = mc->mc_rotor;
|
|
}
|
|
|
|
/*
|
|
* If the hint put us into the wrong metaslab class, or into a
|
|
* metaslab group that has been passivated, just follow the rotor.
|
|
*/
|
|
if (mg->mg_class != mc || mg->mg_activation_count <= 0)
|
|
mg = mc->mc_rotor;
|
|
|
|
rotor = mg;
|
|
top:
|
|
all_zero = B_TRUE;
|
|
do {
|
|
ASSERT(mg->mg_activation_count == 1);
|
|
|
|
vd = mg->mg_vd;
|
|
|
|
/*
|
|
* Don't allocate from faulted devices.
|
|
*/
|
|
if (zio_lock) {
|
|
spa_config_enter(spa, SCL_ZIO, FTAG, RW_READER);
|
|
allocatable = vdev_allocatable(vd);
|
|
spa_config_exit(spa, SCL_ZIO, FTAG);
|
|
} else {
|
|
allocatable = vdev_allocatable(vd);
|
|
}
|
|
|
|
/*
|
|
* Determine if the selected metaslab group is eligible
|
|
* for allocations. If we're ganging or have requested
|
|
* an allocation for the smallest gang block size
|
|
* then we don't want to avoid allocating to the this
|
|
* metaslab group. If we're in this condition we should
|
|
* try to allocate from any device possible so that we
|
|
* don't inadvertently return ENOSPC and suspend the pool
|
|
* even though space is still available.
|
|
*/
|
|
if (allocatable && CAN_FASTGANG(flags) &&
|
|
psize > SPA_GANGBLOCKSIZE)
|
|
allocatable = metaslab_group_allocatable(mg);
|
|
|
|
if (!allocatable)
|
|
goto next;
|
|
|
|
/*
|
|
* Avoid writing single-copy data to a failing vdev
|
|
* unless the user instructs us that it is okay.
|
|
*/
|
|
if ((vd->vdev_stat.vs_write_errors > 0 ||
|
|
vd->vdev_state < VDEV_STATE_HEALTHY) &&
|
|
d == 0 && dshift == 3 && vd->vdev_children == 0) {
|
|
all_zero = B_FALSE;
|
|
goto next;
|
|
}
|
|
|
|
ASSERT(mg->mg_class == mc);
|
|
|
|
distance = vd->vdev_asize >> dshift;
|
|
if (distance <= (1ULL << vd->vdev_ms_shift))
|
|
distance = 0;
|
|
else
|
|
all_zero = B_FALSE;
|
|
|
|
asize = vdev_psize_to_asize(vd, psize);
|
|
ASSERT(P2PHASE(asize, 1ULL << vd->vdev_ashift) == 0);
|
|
|
|
offset = metaslab_group_alloc(mg, psize, asize, txg, distance,
|
|
dva, d);
|
|
if (offset != -1ULL) {
|
|
/*
|
|
* If we've just selected this metaslab group,
|
|
* figure out whether the corresponding vdev is
|
|
* over- or under-used relative to the pool,
|
|
* and set an allocation bias to even it out.
|
|
*
|
|
* Bias is also used to compensate for unequally
|
|
* sized vdevs so that space is allocated fairly.
|
|
*/
|
|
if (mc->mc_aliquot == 0 && metaslab_bias_enabled) {
|
|
vdev_stat_t *vs = &vd->vdev_stat;
|
|
int64_t vs_free = vs->vs_space - vs->vs_alloc;
|
|
int64_t mc_free = mc->mc_space - mc->mc_alloc;
|
|
int64_t ratio;
|
|
|
|
/*
|
|
* Calculate how much more or less we should
|
|
* try to allocate from this device during
|
|
* this iteration around the rotor.
|
|
*
|
|
* This basically introduces a zero-centered
|
|
* bias towards the devices with the most
|
|
* free space, while compensating for vdev
|
|
* size differences.
|
|
*
|
|
* Examples:
|
|
* vdev V1 = 16M/128M
|
|
* vdev V2 = 16M/128M
|
|
* ratio(V1) = 100% ratio(V2) = 100%
|
|
*
|
|
* vdev V1 = 16M/128M
|
|
* vdev V2 = 64M/128M
|
|
* ratio(V1) = 127% ratio(V2) = 72%
|
|
*
|
|
* vdev V1 = 16M/128M
|
|
* vdev V2 = 64M/512M
|
|
* ratio(V1) = 40% ratio(V2) = 160%
|
|
*/
|
|
ratio = (vs_free * mc->mc_alloc_groups * 100) /
|
|
(mc_free + 1);
|
|
mg->mg_bias = ((ratio - 100) *
|
|
(int64_t)mg->mg_aliquot) / 100;
|
|
} else if (!metaslab_bias_enabled) {
|
|
mg->mg_bias = 0;
|
|
}
|
|
|
|
if ((flags & METASLAB_FASTWRITE) ||
|
|
atomic_add_64_nv(&mc->mc_aliquot, asize) >=
|
|
mg->mg_aliquot + mg->mg_bias) {
|
|
mc->mc_rotor = mg->mg_next;
|
|
mc->mc_aliquot = 0;
|
|
}
|
|
|
|
DVA_SET_VDEV(&dva[d], vd->vdev_id);
|
|
DVA_SET_OFFSET(&dva[d], offset);
|
|
DVA_SET_GANG(&dva[d], !!(flags & METASLAB_GANG_HEADER));
|
|
DVA_SET_ASIZE(&dva[d], asize);
|
|
|
|
if (flags & METASLAB_FASTWRITE) {
|
|
atomic_add_64(&vd->vdev_pending_fastwrite,
|
|
psize);
|
|
}
|
|
|
|
return (0);
|
|
}
|
|
next:
|
|
mc->mc_rotor = mg->mg_next;
|
|
mc->mc_aliquot = 0;
|
|
} while ((mg = mg->mg_next) != rotor);
|
|
|
|
if (!all_zero) {
|
|
dshift++;
|
|
ASSERT(dshift < 64);
|
|
goto top;
|
|
}
|
|
|
|
if (!allocatable && !zio_lock) {
|
|
dshift = 3;
|
|
zio_lock = B_TRUE;
|
|
goto top;
|
|
}
|
|
|
|
bzero(&dva[d], sizeof (dva_t));
|
|
|
|
return (SET_ERROR(ENOSPC));
|
|
}
|
|
|
|
/*
|
|
* Free the block represented by DVA in the context of the specified
|
|
* transaction group.
|
|
*/
|
|
static void
|
|
metaslab_free_dva(spa_t *spa, const dva_t *dva, uint64_t txg, boolean_t now)
|
|
{
|
|
uint64_t vdev = DVA_GET_VDEV(dva);
|
|
uint64_t offset = DVA_GET_OFFSET(dva);
|
|
uint64_t size = DVA_GET_ASIZE(dva);
|
|
vdev_t *vd;
|
|
metaslab_t *msp;
|
|
|
|
if (txg > spa_freeze_txg(spa))
|
|
return;
|
|
|
|
if ((vd = vdev_lookup_top(spa, vdev)) == NULL || !DVA_IS_VALID(dva) ||
|
|
(offset >> vd->vdev_ms_shift) >= vd->vdev_ms_count) {
|
|
zfs_panic_recover("metaslab_free_dva(): bad DVA %llu:%llu:%llu",
|
|
(u_longlong_t)vdev, (u_longlong_t)offset,
|
|
(u_longlong_t)size);
|
|
return;
|
|
}
|
|
|
|
msp = vd->vdev_ms[offset >> vd->vdev_ms_shift];
|
|
|
|
if (DVA_GET_GANG(dva))
|
|
size = vdev_psize_to_asize(vd, SPA_GANGBLOCKSIZE);
|
|
|
|
mutex_enter(&msp->ms_lock);
|
|
|
|
if (now) {
|
|
range_tree_remove(msp->ms_alloctree[txg & TXG_MASK],
|
|
offset, size);
|
|
|
|
VERIFY(!msp->ms_condensing);
|
|
VERIFY3U(offset, >=, msp->ms_start);
|
|
VERIFY3U(offset + size, <=, msp->ms_start + msp->ms_size);
|
|
VERIFY3U(range_tree_space(msp->ms_tree) + size, <=,
|
|
msp->ms_size);
|
|
VERIFY0(P2PHASE(offset, 1ULL << vd->vdev_ashift));
|
|
VERIFY0(P2PHASE(size, 1ULL << vd->vdev_ashift));
|
|
range_tree_add(msp->ms_tree, offset, size);
|
|
} else {
|
|
if (range_tree_space(msp->ms_freetree[txg & TXG_MASK]) == 0)
|
|
vdev_dirty(vd, VDD_METASLAB, msp, txg);
|
|
range_tree_add(msp->ms_freetree[txg & TXG_MASK],
|
|
offset, size);
|
|
}
|
|
|
|
mutex_exit(&msp->ms_lock);
|
|
}
|
|
|
|
/*
|
|
* Intent log support: upon opening the pool after a crash, notify the SPA
|
|
* of blocks that the intent log has allocated for immediate write, but
|
|
* which are still considered free by the SPA because the last transaction
|
|
* group didn't commit yet.
|
|
*/
|
|
static int
|
|
metaslab_claim_dva(spa_t *spa, const dva_t *dva, uint64_t txg)
|
|
{
|
|
uint64_t vdev = DVA_GET_VDEV(dva);
|
|
uint64_t offset = DVA_GET_OFFSET(dva);
|
|
uint64_t size = DVA_GET_ASIZE(dva);
|
|
vdev_t *vd;
|
|
metaslab_t *msp;
|
|
int error = 0;
|
|
|
|
ASSERT(DVA_IS_VALID(dva));
|
|
|
|
if ((vd = vdev_lookup_top(spa, vdev)) == NULL ||
|
|
(offset >> vd->vdev_ms_shift) >= vd->vdev_ms_count)
|
|
return (SET_ERROR(ENXIO));
|
|
|
|
msp = vd->vdev_ms[offset >> vd->vdev_ms_shift];
|
|
|
|
if (DVA_GET_GANG(dva))
|
|
size = vdev_psize_to_asize(vd, SPA_GANGBLOCKSIZE);
|
|
|
|
mutex_enter(&msp->ms_lock);
|
|
|
|
if ((txg != 0 && spa_writeable(spa)) || !msp->ms_loaded)
|
|
error = metaslab_activate(msp, METASLAB_WEIGHT_SECONDARY);
|
|
|
|
if (error == 0 && !range_tree_contains(msp->ms_tree, offset, size))
|
|
error = SET_ERROR(ENOENT);
|
|
|
|
if (error || txg == 0) { /* txg == 0 indicates dry run */
|
|
mutex_exit(&msp->ms_lock);
|
|
return (error);
|
|
}
|
|
|
|
VERIFY(!msp->ms_condensing);
|
|
VERIFY0(P2PHASE(offset, 1ULL << vd->vdev_ashift));
|
|
VERIFY0(P2PHASE(size, 1ULL << vd->vdev_ashift));
|
|
VERIFY3U(range_tree_space(msp->ms_tree) - size, <=, msp->ms_size);
|
|
range_tree_remove(msp->ms_tree, offset, size);
|
|
|
|
if (spa_writeable(spa)) { /* don't dirty if we're zdb(1M) */
|
|
if (range_tree_space(msp->ms_alloctree[txg & TXG_MASK]) == 0)
|
|
vdev_dirty(vd, VDD_METASLAB, msp, txg);
|
|
range_tree_add(msp->ms_alloctree[txg & TXG_MASK], offset, size);
|
|
}
|
|
|
|
mutex_exit(&msp->ms_lock);
|
|
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
metaslab_alloc(spa_t *spa, metaslab_class_t *mc, uint64_t psize, blkptr_t *bp,
|
|
int ndvas, uint64_t txg, blkptr_t *hintbp, int flags)
|
|
{
|
|
dva_t *dva = bp->blk_dva;
|
|
dva_t *hintdva = hintbp->blk_dva;
|
|
int d, error = 0;
|
|
|
|
ASSERT(bp->blk_birth == 0);
|
|
ASSERT(BP_PHYSICAL_BIRTH(bp) == 0);
|
|
|
|
spa_config_enter(spa, SCL_ALLOC, FTAG, RW_READER);
|
|
|
|
if (mc->mc_rotor == NULL) { /* no vdevs in this class */
|
|
spa_config_exit(spa, SCL_ALLOC, FTAG);
|
|
return (SET_ERROR(ENOSPC));
|
|
}
|
|
|
|
ASSERT(ndvas > 0 && ndvas <= spa_max_replication(spa));
|
|
ASSERT(BP_GET_NDVAS(bp) == 0);
|
|
ASSERT(hintbp == NULL || ndvas <= BP_GET_NDVAS(hintbp));
|
|
|
|
for (d = 0; d < ndvas; d++) {
|
|
error = metaslab_alloc_dva(spa, mc, psize, dva, d, hintdva,
|
|
txg, flags);
|
|
if (error != 0) {
|
|
for (d--; d >= 0; d--) {
|
|
metaslab_free_dva(spa, &dva[d], txg, B_TRUE);
|
|
bzero(&dva[d], sizeof (dva_t));
|
|
}
|
|
spa_config_exit(spa, SCL_ALLOC, FTAG);
|
|
return (error);
|
|
}
|
|
}
|
|
ASSERT(error == 0);
|
|
ASSERT(BP_GET_NDVAS(bp) == ndvas);
|
|
|
|
spa_config_exit(spa, SCL_ALLOC, FTAG);
|
|
|
|
BP_SET_BIRTH(bp, txg, txg);
|
|
|
|
return (0);
|
|
}
|
|
|
|
void
|
|
metaslab_free(spa_t *spa, const blkptr_t *bp, uint64_t txg, boolean_t now)
|
|
{
|
|
const dva_t *dva = bp->blk_dva;
|
|
int d, ndvas = BP_GET_NDVAS(bp);
|
|
|
|
ASSERT(!BP_IS_HOLE(bp));
|
|
ASSERT(!now || bp->blk_birth >= spa_syncing_txg(spa));
|
|
|
|
spa_config_enter(spa, SCL_FREE, FTAG, RW_READER);
|
|
|
|
for (d = 0; d < ndvas; d++)
|
|
metaslab_free_dva(spa, &dva[d], txg, now);
|
|
|
|
spa_config_exit(spa, SCL_FREE, FTAG);
|
|
}
|
|
|
|
int
|
|
metaslab_claim(spa_t *spa, const blkptr_t *bp, uint64_t txg)
|
|
{
|
|
const dva_t *dva = bp->blk_dva;
|
|
int ndvas = BP_GET_NDVAS(bp);
|
|
int d, error = 0;
|
|
|
|
ASSERT(!BP_IS_HOLE(bp));
|
|
|
|
if (txg != 0) {
|
|
/*
|
|
* First do a dry run to make sure all DVAs are claimable,
|
|
* so we don't have to unwind from partial failures below.
|
|
*/
|
|
if ((error = metaslab_claim(spa, bp, 0)) != 0)
|
|
return (error);
|
|
}
|
|
|
|
spa_config_enter(spa, SCL_ALLOC, FTAG, RW_READER);
|
|
|
|
for (d = 0; d < ndvas; d++)
|
|
if ((error = metaslab_claim_dva(spa, &dva[d], txg)) != 0)
|
|
break;
|
|
|
|
spa_config_exit(spa, SCL_ALLOC, FTAG);
|
|
|
|
ASSERT(error == 0 || txg == 0);
|
|
|
|
return (error);
|
|
}
|
|
|
|
void
|
|
metaslab_fastwrite_mark(spa_t *spa, const blkptr_t *bp)
|
|
{
|
|
const dva_t *dva = bp->blk_dva;
|
|
int ndvas = BP_GET_NDVAS(bp);
|
|
uint64_t psize = BP_GET_PSIZE(bp);
|
|
int d;
|
|
vdev_t *vd;
|
|
|
|
ASSERT(!BP_IS_HOLE(bp));
|
|
ASSERT(!BP_IS_EMBEDDED(bp));
|
|
ASSERT(psize > 0);
|
|
|
|
spa_config_enter(spa, SCL_VDEV, FTAG, RW_READER);
|
|
|
|
for (d = 0; d < ndvas; d++) {
|
|
if ((vd = vdev_lookup_top(spa, DVA_GET_VDEV(&dva[d]))) == NULL)
|
|
continue;
|
|
atomic_add_64(&vd->vdev_pending_fastwrite, psize);
|
|
}
|
|
|
|
spa_config_exit(spa, SCL_VDEV, FTAG);
|
|
}
|
|
|
|
void
|
|
metaslab_fastwrite_unmark(spa_t *spa, const blkptr_t *bp)
|
|
{
|
|
const dva_t *dva = bp->blk_dva;
|
|
int ndvas = BP_GET_NDVAS(bp);
|
|
uint64_t psize = BP_GET_PSIZE(bp);
|
|
int d;
|
|
vdev_t *vd;
|
|
|
|
ASSERT(!BP_IS_HOLE(bp));
|
|
ASSERT(!BP_IS_EMBEDDED(bp));
|
|
ASSERT(psize > 0);
|
|
|
|
spa_config_enter(spa, SCL_VDEV, FTAG, RW_READER);
|
|
|
|
for (d = 0; d < ndvas; d++) {
|
|
if ((vd = vdev_lookup_top(spa, DVA_GET_VDEV(&dva[d]))) == NULL)
|
|
continue;
|
|
ASSERT3U(vd->vdev_pending_fastwrite, >=, psize);
|
|
atomic_sub_64(&vd->vdev_pending_fastwrite, psize);
|
|
}
|
|
|
|
spa_config_exit(spa, SCL_VDEV, FTAG);
|
|
}
|
|
|
|
void
|
|
metaslab_check_free(spa_t *spa, const blkptr_t *bp)
|
|
{
|
|
int i, j;
|
|
|
|
if ((zfs_flags & ZFS_DEBUG_ZIO_FREE) == 0)
|
|
return;
|
|
|
|
spa_config_enter(spa, SCL_VDEV, FTAG, RW_READER);
|
|
for (i = 0; i < BP_GET_NDVAS(bp); i++) {
|
|
uint64_t vdev = DVA_GET_VDEV(&bp->blk_dva[i]);
|
|
vdev_t *vd = vdev_lookup_top(spa, vdev);
|
|
uint64_t offset = DVA_GET_OFFSET(&bp->blk_dva[i]);
|
|
uint64_t size = DVA_GET_ASIZE(&bp->blk_dva[i]);
|
|
metaslab_t *msp = vd->vdev_ms[offset >> vd->vdev_ms_shift];
|
|
|
|
if (msp->ms_loaded)
|
|
range_tree_verify(msp->ms_tree, offset, size);
|
|
|
|
for (j = 0; j < TXG_SIZE; j++)
|
|
range_tree_verify(msp->ms_freetree[j], offset, size);
|
|
for (j = 0; j < TXG_DEFER_SIZE; j++)
|
|
range_tree_verify(msp->ms_defertree[j], offset, size);
|
|
}
|
|
spa_config_exit(spa, SCL_VDEV, FTAG);
|
|
}
|
|
|
|
#if defined(_KERNEL) && defined(HAVE_SPL)
|
|
module_param(metaslab_aliquot, ulong, 0644);
|
|
module_param(metaslab_debug_load, int, 0644);
|
|
module_param(metaslab_debug_unload, int, 0644);
|
|
module_param(metaslab_preload_enabled, int, 0644);
|
|
module_param(zfs_mg_noalloc_threshold, int, 0644);
|
|
module_param(zfs_mg_fragmentation_threshold, int, 0644);
|
|
module_param(zfs_metaslab_fragmentation_threshold, int, 0644);
|
|
module_param(metaslab_fragmentation_factor_enabled, int, 0644);
|
|
module_param(metaslab_lba_weighting_enabled, int, 0644);
|
|
module_param(metaslab_bias_enabled, int, 0644);
|
|
|
|
MODULE_PARM_DESC(metaslab_aliquot,
|
|
"allocation granularity (a.k.a. stripe size)");
|
|
MODULE_PARM_DESC(metaslab_debug_load,
|
|
"load all metaslabs when pool is first opened");
|
|
MODULE_PARM_DESC(metaslab_debug_unload,
|
|
"prevent metaslabs from being unloaded");
|
|
MODULE_PARM_DESC(metaslab_preload_enabled,
|
|
"preload potential metaslabs during reassessment");
|
|
|
|
MODULE_PARM_DESC(zfs_mg_noalloc_threshold,
|
|
"percentage of free space for metaslab group to allow allocation");
|
|
MODULE_PARM_DESC(zfs_mg_fragmentation_threshold,
|
|
"fragmentation for metaslab group to allow allocation");
|
|
|
|
MODULE_PARM_DESC(zfs_metaslab_fragmentation_threshold,
|
|
"fragmentation for metaslab to allow allocation");
|
|
MODULE_PARM_DESC(metaslab_fragmentation_factor_enabled,
|
|
"use the fragmentation metric to prefer less fragmented metaslabs");
|
|
MODULE_PARM_DESC(metaslab_lba_weighting_enabled,
|
|
"prefer metaslabs with lower LBAs");
|
|
MODULE_PARM_DESC(metaslab_bias_enabled,
|
|
"enable metaslab group biasing");
|
|
#endif /* _KERNEL && HAVE_SPL */
|