Commit Graph

1668 Commits

Author SHA1 Message Date
Mark Johnston
d7965243c1 Re-compute the ARC size before computing the MFU target.
This fixes an upstream regression introduced in r331404, causing overly
aggressive reclamation of the ARC when under pressure.

Diagnosed by:	Paul <devgs@ukr.net>
Approved by:	re (gjb)
MFC after:	3 days
2018-08-31 21:45:05 +00:00
Mark Johnston
f554293615 Re-add kstat.zfs.misc.arcstats.other_size under COMPAT_FREEBSD11.
It is used by a number of applications, notably top(1).

Reported by:	netchild
Reviewed by:	allanjude
Approved by:	re (delphij)
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D16943
2018-08-30 13:42:01 +00:00
Konstantin Belousov
f0165b1ca6 Remove {max/min}_offset() macros, use vm_map_{max/min}() inlines.
Exposing max_offset and min_offset defines in public headers is
causing clashes with variable names, for example when building QEMU.

Based on the submission by:	royger
Reviewed by:	alc, markj (previous version)
Sponsored by:	The FreeBSD Foundation (kib)
MFC after:	1 week
Approved by:	re (marius)
Differential revision:	https://reviews.freebsd.org/D16881
2018-08-29 12:24:19 +00:00
Mark Johnston
394e8d20d9 Add a sysctl for the ZFS abd_scatter_enabled setting.
Submitted by:	Yamagi Burmeister <lists@yamagi.org> (original version)
Approved by:	re (rgrimes)
MFC after:	3 days
2018-08-29 02:49:18 +00:00
Alexander Motin
cb892a4117 Unblock speculative prefetcher also on pool creation.
Fix at r331950 appeared to be incomplete, fixing only case of pool
import, but not pool creation, leaving prefetcher still blocked for
newly created pools.

Approved by:	re (gjb)
MFC after:	1 week
2018-08-24 01:59:25 +00:00
Alexander Motin
2efb7660b5 Add dmu_tx_assign() error handling in zfs_unlinked_drain().
The error handling got lost during r334810, while according to the report
error there may happen in case of dataset being over quota.  In such case
just leave the node in the unlinked list to be freed sometimes later.

PR:		229887
Sponsored by:	iXsystems, Inc.
2018-08-22 16:32:53 +00:00
Alexander Motin
6128ca8683 Create separate taskqueue to call zfs_unlinked_drain().
r334810 introduced zfs_unlinked_drain() dispatch to taskqueue on every
deletion of a file with extended attributes.  Using system_taskq for that
with its multiple threads in case of multiple files deletion caused all
available CPU threads to uselessly spin on busy locks, completely blocking
the system.

Use of single dedicated taskqueue is the only easy solution I've found,
while in would be great if we could specify that some task should be
executed only once at a time, but never in parallel, while many tasks
could use different threads same time.

Sponsored by:	iXsystems, Inc.
2018-08-22 16:27:24 +00:00
Mark Johnston
b1a90834bb Set arc_kmem_cache_reap_retry_ms to 0 and make it configurable.
r329759 introduced this parameter, which controls the rate at which ZFS
UMA zones are drained when the ARC reclaim thread is shrinking the ARC.
The reclamation target is derived from the global free page count, and
arc_shrink() only frees buffers back to UMA, so the free page count is
not updated until the zones are drained.  Thus, back-to-back calls to
arc_shrink() within the arc_kmem_cache_reap_retry_ms interval do not
provide immediate feedback to the arc_reclaim control loop, so we may
free more of the ARC than needed to address a transient page shortage.

As we do not implement the asynchronous zone draining added in r329759,
disable the retry interval, restoring pre-r329759 behaviour.  That is,
we will drain the ZFS UMA zones before each attempt to shrink the ARC.

Reviewed by:	mav
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
2018-08-21 16:37:37 +00:00
Matt Macy
d12e91d584 Make dnode definition uniform on !x86
gcc4 requires -fms-extensions to accept anonymous union members
2018-08-21 03:45:09 +00:00
Alexander Motin
cd2315086a 9751 Allocation throttling misplacing ditto blocks
Relax allocation throttling for ditto blocks.  Due to random imbalances
in allocation it tends to push block copies to one vdev, that looks
slightly better at the moment.  Slightly less strict policy allows both
improve data security and surprisingly write performance, since we don't
need to touch extra metaslabs on each vdev to respect the min distance.

Sponsored by:	iXsystems, Inc.
2018-08-17 15:17:09 +00:00
Alexander Motin
a8e93e3cd7 9738 Fix third block copy allocations, broken at 9112.
Use METASLAB_WEIGHT_CLAIM weight to allocate tertiary blocks.
Previous use of METASLAB_WEIGHT_SECONDARY for that caused errors
later on metaslab_activate_allocator() call, leading to massive
load of unneeded metaslabs and write freezes.

Reviewed by:	Paul Dagnelie <pcd@delphix.com>
2018-08-17 15:00:41 +00:00
Alexander Motin
6d14f2c48f Make vfs.zfs.zio.dva_throttle_enabled sysctl writable.
Not sure what I thought originally, but as I see now runtime changes are
working fine, and the code seems like even designed for this.
2018-08-16 18:44:50 +00:00
Jamie Gritton
284001a222 Put jail(2) under COMPAT_FREEBSD11. It has been the "old" way of creating
jails since FreeBSD 7.

Along with the system call, put the various security.jail.allow_foo and
security.jail.foo_allowed sysctls partly under COMPAT_FREEBSD11 (or
BURN_BRIDGES).  These sysctls had two disparate uses: on the system side,
they were global permissions for jails created via jail(2) which lacked
fine-grained permission controls; inside a jail, they're read-only
descriptions of what the current jail is allowed to do.  The first use
is obsolete along with jail(2), but keep them for the second-read-only use.

Differential Revision:	D14791
2018-08-16 18:40:16 +00:00
Alexander Motin
edc391e922 Add couple tunables/sysctl, missed in r336949. 2018-08-16 00:50:14 +00:00
Alexander Motin
8ce70dfcfa Fix mismerge in r337196.
ZoL did the same mistake, and fixed it with separate commit 863522b1f9:

dsl_scan_scrub_cb: don't double-account non-embedded blocks

We were doing count_block() twice inside this function, once
unconditionally at the beginning (intended to catch the embedded block
case) and once near the end after processing the block.

The double-accounting caused the "zpool scrub" progress statistics in
"zpool status" to climb from 0% to 200% instead of 0% to 100%, and
showed double the I/O rate it was actually seeing.

This was apparently a regression introduced in commit 00c405b4b5,
which was an incorrect port of this OpenZFS commit:

    https://github.com/openzfs/openzfs/commit/d8a447a7

Reviewed by: Thomas Caputi <tcaputi@datto.com>
Reviewed by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Signed-off-by: Steven Noonan <steven@uplinklabs.net>
Closes #7720
Closes #7738

Reported by:	sef
2018-08-15 21:01:57 +00:00
Matt Macy
fb8f55f586 MFV/ZoL: Add dbuf hash and dbuf cache kstats
TODO: KSTAT_TYPE_NAMED support

commit 5e021f56d3
Author: Giuseppe Di Natale <dinatale2@users.noreply.github.com>
Date:   Mon Jan 29 10:24:52 2018 -0800

    Add dbuf hash and dbuf cache kstats

    Introduce kstats about the dbuf hash and dbuf cache
    to make it easier to inspect state. This should help
    with debugging and understanding of these portions
    of the codebase.

    Correct format of dbuf kstat file.

    Introduce a dbc column to dbufs kstat to indicate if
    a dbuf is in the dbuf cache.

    Introduce field filtering in the dbufstat python script.

    Introduce a no header option to the dbufstat python script.

    Introduce a test case to test basic mru->mfu list movement
    in the ARC.

    Reviewed-by: Tony Hutter <hutter2@llnl.gov>
    Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
    Signed-off-by: Giuseppe Di Natale <dinatale2@llnl.gov>
    Closes #6906
2018-08-12 03:15:30 +00:00
Matt Macy
13ae5c6ba8 MFV/ZoL: Fix stack dbuf_hold_impl()
commit fc5bb51f08
Author: Brian Behlendorf <behlendorf1@llnl.gov>
Date:   Thu Aug 26 10:52:00 2010 -0700

    Fix stack dbuf_hold_impl()

    This commit preserves the recursive function dbuf_hold_impl() but moves
    the local variables and function arguments to the heap to minimize
    the stack frame size.  Enough space is initially allocated on the
    stack for 20 levels of recursion.  This technique was based on commit
    34229a2f2ac07363f64ddd63e014964fff2f0671 which reduced stack usage of
    traverse_visitbp().

    Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2018-08-12 02:24:18 +00:00
Matt Macy
6e3d1345d9 fix build DN_MAX_BONUSLEN -> DN_OLD_MAX_BONUSLEN 2018-08-12 02:12:44 +00:00
Matt Macy
0f5add2566 Restore legacy dnode_phys layout on tier 2 arches
Evidently gcc4 doesn't support anonymous union members
2018-08-12 02:09:06 +00:00
Matt Macy
104ed324dd MFV/ZoL: Fix stack noinline
commit 60948de1ef
Author: Brian Behlendorf <behlendorf1@llnl.gov>
Date:   Thu Aug 26 10:58:36 2010 -0700

    Fix stack noinline

    Certain function must never be automatically inlined by gcc because
    they are stack heavy or called recursively.  This patch flags all
    such functions I've found as 'noinline' to prevent gcc from making
    the optimization.

    Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2018-08-12 01:29:30 +00:00
Matt Macy
71d48dbda3 MFV/ZoL: Fix PANIC: metaslab_free_dva(): bad DVA X:Y:Z
commit 81edd3e834
Author: Peng <peng.hse@xtaotech.com>
Date:   Wed Jun 8 15:22:07 2016 +0800

    Fix PANIC: metaslab_free_dva(): bad DVA X:Y:Z

    The following scenario can result in garbage in the dn_spill field.
    The db->db_blkptr must be set to NULL when DNODE_FLAG_SPILL_BLKPTR
    is clear to ensure the dn_spill field is cleared.

    Current txg = A.
    * A new spill buffer is created. Its dbuf is initialized with
      db_blkptr = NULL and it's dirtied.

    Current txg = B.
    * The spill buffer is modified. It's marked as dirty in this txg.
    * Additional changes make the spill buffer unnecessary because the
      xattr fits into the bonus buffer, so it's removed. The dbuf is
      undirtied in this txg, but it's still referenced and cannot be
      destroyed.

    Current txg = C.
    * Starts syncing of txg A
    * dbuf_sync_leaf() is called for the spill buffer. Since db_blkptr
      is NULL, dbuf_check_blkptr() is called.
    * The dbuf starts being written and it reaches the ready state
      (not done yet).
    * A new change makes the spill buffer necessary again.
      sa_build_layouts() ends up calling dbuf_find() to locate the
      dbuf.  It finds the old dbuf because it has not been destroyed yet
      (it will be destroyed when the previous write is done and there
      are no more references). The old dbuf has db_blkptr != NULL.
    * txg A write is complete and the dbuf released. However it's still
      referenced, so it's not destroyed.

    Current txg = D.
    * Starts syncing of txg B
    * dbuf_sync_leaf() is called for the bonus buffer. Its contents are
      directly copied into the dnode, overwriting the blkptr area because,
      in txg B, the bonus buffer was big enough to hold the entire xattr.
    * At this point, the db_blkptr of the spill buffer used in txg C
      gets corrupted.

    Signed-off-by: Peng <peng.hse@xtaotech.com>
    Signed-off-by: Tim Chase <tim@chase2k.com>
    Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
    Closes #3937
2018-08-12 01:17:32 +00:00
Matt Macy
6f06a36d47 MFV/ZoL: add dbuf stats
NB: disabled pending the addition of KSTAT_TYPE_RAW support to the
SPL

commit e0b0ca983d
Author: Brian Behlendorf <behlendorf1@llnl.gov>
Date:   Wed Oct 2 17:11:19 2013 -0700

    Add visibility in to cached dbufs

    Currently there is no mechanism to inspect which dbufs are being
    cached by the system.  There are some coarse counters in arcstats
    by they only give a rough idea of what's being cached.  This patch
    aims to improve the current situation by adding a new dbufs kstat.

    When read this new kstat will walk all cached dbufs linked in to
    the dbuf_hash.  For each dbuf it will dump detailed information
    about the buffer.  It will also dump additional information about
    the referenced arc buffer and its related dnode.  This provides a
    more complete view in to exactly what is being cached.

    With this generic infrastructure in place utilities can be written
    to post-process the data to understand exactly how the caching is
    working.  For example, the data could be processed to show a list
    of all cached dnodes and how much space they're consuming.  Or a
    similar list could be generated based on dnode type.  Many other
    ways to interpret the data exist based on what kinds of questions
    you're trying to answer.

    Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
    Signed-off-by: Prakash Surya <surya1@llnl.gov>
2018-08-12 01:10:18 +00:00
Matt Macy
cc0fbbb92e MFV/ZoL: Implement large_dnode pool feature
commit 50c957f702
Author: Ned Bass <bass6@llnl.gov>
Date:   Wed Mar 16 18:25:34 2016 -0700

    Implement large_dnode pool feature

    Justification
    -------------

    This feature adds support for variable length dnodes. Our motivation is
    to eliminate the overhead associated with using spill blocks.  Spill
    blocks are used to store system attribute data (i.e. file metadata) that
    does not fit in the dnode's bonus buffer. By allowing a larger bonus
    buffer area the use of a spill block can be avoided.  Spill blocks
    potentially incur an additional read I/O for every dnode in a dnode
    block. As a worst case example, reading 32 dnodes from a 16k dnode block
    and all of the spill blocks could issue 33 separate reads. Now suppose
    those dnodes have size 1024 and therefore don't need spill blocks.  Then
    the worst case number of blocks read is reduced to from 33 to two--one
    per dnode block. In practice spill blocks may tend to be co-located on
    disk with the dnode blocks so the reduction in I/O would not be this
    drastic. In a badly fragmented pool, however, the improvement could be
    significant.

    ZFS-on-Linux systems that make heavy use of extended attributes would
    benefit from this feature. In particular, ZFS-on-Linux supports the
    xattr=sa dataset property which allows file extended attribute data
    to be stored in the dnode bonus buffer as an alternative to the
    traditional directory-based format. Workloads such as SELinux and the
    Lustre distributed filesystem often store enough xattr data to force
    spill bocks when xattr=sa is in effect. Large dnodes may therefore
    provide a performance benefit to such systems.

    Other use cases that may benefit from this feature include files with
    large ACLs and symbolic links with long target names. Furthermore,
    this feature may be desirable on other platforms in case future
    applications or features are developed that could make use of a
    larger bonus buffer area.

    Implementation
    --------------

    The size of a dnode may be a multiple of 512 bytes up to the size of
    a dnode block (currently 16384 bytes). A dn_extra_slots field was
    added to the current on-disk dnode_phys_t structure to describe the
    size of the physical dnode on disk. The 8 bits for this field were
    taken from the zero filled dn_pad2 field. The field represents how
    many "extra" dnode_phys_t slots a dnode consumes in its dnode block.
    This convention results in a value of 0 for 512 byte dnodes which
    preserves on-disk format compatibility with older software.

    Similarly, the in-memory dnode_t structure has a new dn_num_slots field
    to represent the total number of dnode_phys_t slots consumed on disk.
    Thus dn->dn_num_slots is 1 greater than the corresponding
    dnp->dn_extra_slots. This difference in convention was adopted
    because, unlike on-disk structures, backward compatibility is not a
    concern for in-memory objects, so we used a more natural way to
    represent size for a dnode_t.

    The default size for newly created dnodes is determined by the value of
    a new "dnodesize" dataset property. By default the property is set to
    "legacy" which is compatible with older software. Setting the property
    to "auto" will allow the filesystem to choose the most suitable dnode
    size. Currently this just sets the default dnode size to 1k, but future
    code improvements could dynamically choose a size based on observed
    workload patterns. Dnodes of varying sizes can coexist within the same
    dataset and even within the same dnode block. For example, to enable
    automatically-sized dnodes, run

     # zfs set dnodesize=auto tank/fish

    The user can also specify literal values for the dnodesize property.
    These are currently limited to powers of two from 1k to 16k. The
    power-of-2 limitation is only for simplicity of the user interface.
    Internally the implementation can handle any multiple of 512 up to 16k,
    and consumers of the DMU API can specify any legal dnode value.

    The size of a new dnode is determined at object allocation time and
    stored as a new field in the znode in-memory structure. New DMU
    interfaces are added to allow the consumer to specify the dnode size
    that a newly allocated object should use. Existing interfaces are
    unchanged to avoid having to update every call site and to preserve
    compatibility with external consumers such as Lustre. The new
    interfaces names are given below. The versions of these functions that
    don't take a dnodesize parameter now just call the _dnsize() versions
    with a dnodesize of 0, which means use the legacy dnode size.

    New DMU interfaces:
      dmu_object_alloc_dnsize()
      dmu_object_claim_dnsize()
      dmu_object_reclaim_dnsize()

    New ZAP interfaces:
      zap_create_dnsize()
      zap_create_norm_dnsize()
      zap_create_flags_dnsize()
      zap_create_claim_norm_dnsize()
      zap_create_link_dnsize()

    The constant DN_MAX_BONUSLEN is renamed to DN_OLD_MAX_BONUSLEN. The
    spa_maxdnodesize() function should be used to determine the maximum
    bonus length for a pool.

    These are a few noteworthy changes to key functions:

    * The prototype for dnode_hold_impl() now takes a "slots" parameter.
      When the DNODE_MUST_BE_FREE flag is set, this parameter is used to
      ensure the hole at the specified object offset is large enough to
      hold the dnode being created. The slots parameter is also used
      to ensure a dnode does not span multiple dnode blocks. In both of
      these cases, if a failure occurs, ENOSPC is returned. Keep in mind,
      these failure cases are only possible when using DNODE_MUST_BE_FREE.

      If the DNODE_MUST_BE_ALLOCATED flag is set, "slots" must be 0.
      dnode_hold_impl() will check if the requested dnode is already
      consumed as an extra dnode slot by an large dnode, in which case
      it returns ENOENT.

    * The function dmu_object_alloc() advances to the next dnode block
      if dnode_hold_impl() returns an error for a requested object.
      This is because the beginning of the next dnode block is the only
      location it can safely assume to either be a hole or a valid
      starting point for a dnode.

    * dnode_next_offset_level() and other functions that iterate
      through dnode blocks may no longer use a simple array indexing
      scheme. These now use the current dnode's dn_num_slots field to
      advance to the next dnode in the block. This is to ensure we
      properly skip the current dnode's bonus area and don't interpret it
      as a valid dnode.

    zdb
    ---
    The zdb command was updated to display a dnode's size under the
    "dnsize" column when the object is dumped.

    For ZIL create log records, zdb will now display the slot count for
    the object.

    ztest
    -----
    Ztest chooses a random dnodesize for every newly created object. The
    random distribution is more heavily weighted toward small dnodes to
    better simulate real-world datasets.

    Unused bonus buffer space is filled with non-zero values computed from
    the object number, dataset id, offset, and generation number.  This
    helps ensure that the dnode traversal code properly skips the interior
    regions of large dnodes, and that these interior regions are not
    overwritten by data belonging to other dnodes. A new test visits each
    object in a dataset. It verifies that the actual dnode size matches what
    was stored in the ztest block tag when it was created. It also verifies
    that the unused bonus buffer space is filled with the expected data
    patterns.

    ZFS Test Suite
    --------------
    Added six new large dnode-specific tests, and integrated the dnodesize
    property into existing tests for zfs allow and send/recv.

    Send/Receive
    ------------
    ZFS send streams for datasets containing large dnodes cannot be received
    on pools that don't support the large_dnode feature. A send stream with
    large dnodes sets a DMU_BACKUP_FEATURE_LARGE_DNODE flag which will be
    unrecognized by an incompatible receiving pool so that the zfs receive
    will fail gracefully.

    While not implemented here, it may be possible to generate a
    backward-compatible send stream from a dataset containing large
    dnodes. The implementation may be tricky, however, because the send
    object record for a large dnode would need to be resized to a 512
    byte dnode, possibly kicking in a spill block in the process. This
    means we would need to construct a new SA layout and possibly
    register it in the SA layout object. The SA layout is normally just
    sent as an ordinary object record. But if we are constructing new
    layouts while generating the send stream we'd have to build the SA
    layout object dynamically and send it at the end of the stream.

    For sending and receiving between pools that do support large dnodes,
    the drr_object send record type is extended with a new field to store
    the dnode slot count. This field was repurposed from unused padding
    in the structure.

    ZIL Replay
    ----------
    The dnode slot count is stored in the uppermost 8 bits of the lr_foid
    field. The bits were unused as the object id is currently capped at
    48 bits.

    Resizing Dnodes
    ---------------
    It should be possible to resize a dnode when it is dirtied if the
    current dnodesize dataset property differs from the dnode's size, but
    this functionality is not currently implemented. Clearly a dnode can
    only grow if there are sufficient contiguous unused slots in the
    dnode block, but it should always be possible to shrink a dnode.
    Growing dnodes may be useful to reduce fragmentation in a pool with
    many spill blocks in use. Shrinking dnodes may be useful to allow
    sending a dataset to a pool that doesn't support the large_dnode
    feature.

    Feature Reference Counting
    --------------------------
    The reference count for the large_dnode pool feature tracks the
    number of datasets that have ever contained a dnode of size larger
    than 512 bytes. The first time a large dnode is created in a dataset
    the dataset is converted to an extensible dataset. This is a one-way
    operation and the only way to decrement the feature count is to
    destroy the dataset, even if the dataset no longer contains any large
    dnodes. The complexity of reference counting on a per-dnode basis was
    too high, so we chose to track it on a per-dataset basis similarly to
    the large_block feature.

    Signed-off-by: Ned Bass <bass6@llnl.gov>
    Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
    Closes #3542
2018-08-12 00:45:53 +00:00
Matt Macy
9f3a171221 Enable balanced arc pruning
Taken from:
ommit f604673836
Author: Brian Behlendorf <behlendorf1@llnl.gov>
Date:   Sat May 30 09:57:53 2015 -0500

    Make arc_prune() asynchronous

    As described in the comment above arc_adapt_thread() it is critical
    that the arc_adapt_thread() function never sleep while holding a hash
    lock.  This behavior was possible in the Linux implementation because
    the arc_prune() logic was implemented to be synchronous.  Under
    illumos the analogous dnlc_reduce_cache() function is asynchronous.

    To address this the arc_do_user_prune() function is has been reworked
    in to two new functions as follows:

    * arc_prune_async() is an asynchronous implementation which dispatches
    the prune callback to be run by the system taskq.  This makes it
    suitable to use in the context of the arc_adapt_thread().

    * arc_prune() is a synchronous implementation which depends on the
    arc_prune_async() implementation but blocks until the outstanding
    callbacks complete.  This is used in arc_kmem_reap_now() where it
    is safe, and expected, that memory will be freed.

    This patch additionally adds the zfs_arc_meta_strategy module option
    while allows the meta reclaim strategy to be configured.  It defaults
    to a balanced strategy which has been proved to work well under Linux
    but the illumos meta-only strategy can be enabled.

    Signed-off-by: Tim Chase <tim@chase2k.com>
    Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2018-08-11 22:01:52 +00:00
Matt Macy
d815f5ba09 buildworld fix: private appears to have special meaning on FreeBSD - revert to priv 2018-08-11 20:41:42 +00:00
Matt Macy
6b55e6fb04 Limit the amount of dnode metadata in the ARC
In addition import most recent arc_prune_async implementation as dependency

commit 25458cbef9
Author: Tim Chase <tim@chase2k.com>
Date:   Wed Jul 13 07:42:40 2016 -0500

    Limit the amount of dnode metadata in the ARC

    Metadata-intensive workloads can cause the ARC to become permanently
    filled with dnode_t objects as they're pinned by the VFS layer.
    Subsequent data-intensive workloads may only benefit from about
    25% of the potential ARC (arc_c_max - arc_meta_limit).

    In order to help track metadata usage more precisely, the other_size
    metadata arcstat has replaced with dbuf_size, dnode_size and bonus_size.

    The new zfs_arc_dnode_limit tunable, which defaults to 10% of
    zfs_arc_meta_limit, defines the minimum number of bytes which is desirable
    to be consumed by dnodes.  Attempts to evict non-metadata will trigger
    async prune tasks if the space used by dnodes exceeds this limit.

    The new zfs_arc_dnode_reduce_percent tunable specifies the amount by
    which the excess dnode space is attempted to be pruned as a percentage of
    the amount by which zfs_arc_dnode_limit is being exceeded.  By default,
    it tries to unpin 10% of the dnodes.

    The problem of dnode metadata pinning was observed with the following
    testing procedure (in this example, zfs_arc_max is set to 4GiB):

        - Create a large number of small files until arc_meta_used exceeds
          arc_meta_limit (3GiB with default tuning) and arc_prune
          starts increasing.

        - Create a 3GiB file with dd.  Observe arc_mata_used.  It will still
          be around 3GiB.

        - Repeatedly read the 3GiB file and observe arc_meta_limit as before.
          It will continue to stay around 3GiB.

    With this modification, space for the 3GiB file is gradually made
    available as subsequent demands on the ARC are made.  The previous behavior
    can be restored by setting zfs_arc_dnode_limit to the same value as the
    zfs_arc_meta_limit.

    Signed-off-by: Tim Chase <tim@chase2k.com>
    Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
    Issue #4345
    Issue #4512
    Issue #4773
    Closes #4858
2018-08-11 19:45:04 +00:00
Matt Macy
90df93417e ZFS/MFV: Use cached feature info in spa_add_feature_stats()
commit 417104bdd3
Author: Ned Bass <bass6@llnl.gov>
Date:   Thu Feb 26 12:24:11 2015 -0800

    Use cached feature info in spa_add_feature_stats()

    Avoid issuing I/O to the pool when retrieving feature flags information.
    Trying to read the ZAPs from disk means that zpool clear would hang if
    the pool is suspended and recovery would require a reboot. To keep the
    feature stats resident in memory, we hang a cached nvlist off of the
    spa.  It is built up from disk the first time spa_add_feature_stats() is
    called, and refreshed thereafter using the cached feature reference
    counts. spa_add_feature_stats() gets called at pool import time so we
    can be sure the cached nvlist will be available if the pool is later
    suspended.

    Signed-off-by: Ned Bass <bass6@llnl.gov>
    Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
    Closes #3082
2018-08-10 23:42:11 +00:00
Matt Macy
648cfe57fd Performance optimization of AVL tree comparator functions
MFV:
commit ee36c709c3
Author: Gvozden Neskovic <neskovic@gmail.com>
Date:   Sat Aug 27 20:12:53 2016 +0200

    perf: 2.75x faster ddt_entry_compare()
        First 256bits of ddt_key_t is a block checksum, which are expected
    to be close to random data. Hence, on average, comparison only needs to
    look at first few bytes of the keys. To reduce number of conditional
    jump instructions, the result is computed as: sign(memcmp(k1, k2)).

    Sign of an integer 'a' can be obtained as: `(0 < a) - (a < 0)` := {-1, 0, 1} ,
    which is computed efficiently.  Synthetic performance evaluation of
    original and new algorithm over 1G random keys on 2.6GHz Intel(R) Xeon(R)
    CPU E5-2660 v3:

    old     6.85789 s
    new     2.49089 s

    perf: 2.8x faster vdev_queue_offset_compare() and vdev_queue_timestamp_compare()
        Compute the result directly instead of using conditionals

    perf: zfs_range_compare()
        Speedup between 1.1x - 2.5x, depending on compiler version and
    optimization level.

    perf: spa_error_entry_compare()
        `bcmp()` is not suitable for comparator use. Use `memcmp()` instead.

    perf: 2.8x faster metaslab_compare() and metaslab_rangesize_compare()
    perf: 2.8x faster zil_bp_compare()
    perf: 2.8x faster mze_compare()
    perf: faster dbuf_compare()
    perf: faster compares in spa_misc
    perf: 2.8x faster layout_hash_compare()
    perf: 2.8x faster space_reftree_compare()
    perf: libzfs: faster avl tree comparators
    perf: guid_compare()
    perf: dsl_deadlist_compare()
    perf: perm_set_compare()
    perf: 2x faster range_tree_seg_compare()
    perf: faster unique_compare()
    perf: faster vdev_cache _compare()
    perf: faster vdev_uberblock_compare()
    perf: faster fuid _compare()
    perf: faster zfs_znode_hold_compare()

    Signed-off-by: Gvozden Neskovic <neskovic@gmail.com>
    Signed-off-by: Richard Elling <richard.elling@gmail.com>
    Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
    Closes #5033
2018-08-10 06:42:08 +00:00
Alexander Motin
f58c851d32 Reduce taskq and context-switch cost of zio pipe
When doing a read from disk, ZFS creates 3 ZIO's: a zio_null(), the
logical zio_read(), and then a physical zio. Currently, each of these
results in a separate taskq_dispatch(zio_execute).

On high-read-iops workloads, this causes a significant performance
impact. By processing all 3 ZIO's in a single taskq entry, we reduce the
overhead on taskq locking and context switching.  We accomplish this by
allowing zio_done() to return a "next zio to execute" to zio_execute().

This results in a ~12% performance increase for random reads, from
96,000 iops to 108,000 iops (with recordsize=8k, on SSD's).

Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed by: George Wilson <george.wilson@delphix.com>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
External-issue: DLPX-59292
Closes #7736

zfsonlinux/zfs@62840030a7
2018-08-03 02:16:45 +00:00
Alexander Motin
07ddc55096 MFV r337223:
9580 Add a hash-table on top of nvlist to speed-up operations

illumos/illumos-gate@2ec7644aab

Reviewed by: Matt Ahrens <matt@delphix.com>
Reviewed by: Sebastien Roy <sebastien.roy@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Serapheim Dimitropoulos <serapheim@delphix.com>
2018-08-03 01:52:25 +00:00
Alexander Motin
420a1ab349 MFV r337220: 8375 Kernel memory leak in nvpair code
illumos/illumos-gate@843c2111b1

Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Prashanth Sreenivasa <pks@delphix.com>
Reviewed by: Robert Mustacchi <rm@joyent.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: Matthew Ahrens <mahrens@delphix.com>
2018-08-03 01:30:03 +00:00
Alexander Motin
33bdecc5d0 MFV r337218: 7261 nvlist code should enforce name length limit
illumos/illumos-gate@48dd5e630c

Reviewed by: Sebastien Roy <sebastien.roy@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Robert Mustacchi <rm@joyent.com>
Approved by: Dan McDonald <danmcd@omniti.com>
Author: Matthew Ahrens <mahrens@delphix.com>
2018-08-03 01:26:07 +00:00
Alexander Motin
c8c51346f5 MFV r337216: 7263 deeply nested nvlist can overflow stack
illumos/illumos-gate@9ca527c3d3

Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Robert Mustacchi <rm@joyent.com>
Approved by: Dan McDonald <danmcd@omniti.com>
Author: Matthew Ahrens <mahrens@delphix.com>
2018-08-03 01:09:12 +00:00
Alexander Motin
0285589b38 MFV 337214:
9621 Make createtxg and guid properties public

illumos/illumos-gate@e8d4a73c86

Reviewed by: Andy Stormont <astormont@racktopsystems.com>
Reviewed by: Paul Dagnelie <pcd@delphix.com>
Reviewed by: Matt Ahrens <matt@delphix.com>
Reviewed by: Yuri Pankov <yuripv@yuripv.net>
Approved by: Robert Mustacchi <rm@joyent.com>
Author:     Josh Paetzel <josh@tcbug.org>
2018-08-03 00:24:27 +00:00
Alexander Motin
54b838a67c MFV r337212:
9465 ARC check for 'anon_size > arc_c/2' can stall the system

illumos/illumos-gate@abe1fd01ce

Reviewed by: Sebastien Roy <sebastien.roy@delphix.com>
Reviewed by: Matt Ahrens <matt@delphix.com>
Reviewed by: Prashanth Sreenivasa <pks@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author:     Don Brady <don.brady@delphix.com>
2018-08-03 00:14:36 +00:00
Alexander Motin
904eaff3f7 MFV r337210: 9577 remove zfs_dbuf_evict_key tsd
The zfs_dbuf_evict_key TSD (thread-specific data) is not necessary - we can
instead pass a flag down in a few places to prevent recursive dbuf eviction.
Making this change has 3 benefits:

1. The code semantics are easier to understand.
2. On Linux, performance is improved, because creating/removing TSD values
(by setting to NULL vs non-NULL) is expensive, and we do it very often.
3. According to Nexenta, the current semantics can cause a deadlock when
concurrently calling dmu_objset_evict_dbufs() (which is rare today, but they
are working on a "parallel unmount" change that triggers this more easily)

illumos/illumos-gate@c2919acbea

Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Serapheim Dimitropoulos <serapheim.dimitro@delphix.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed by: Andy Stormont <astormont@racktopsystems.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
Author:     Matthew Ahrens <mahrens@delphix.com>
2018-08-03 00:01:48 +00:00
Alexander Motin
63ddf13e0d MFV r337208: 9591 ms_shift can be incorrectly changed in MOS config for
indirect vdevs that have been historically expanded

illumos/illumos-gate@11f6a9680e

Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <gwilson@zfsmail.com>
Reviewed by: John Kennedy <john.kennedy@delphix.com>
Reviewed by: Prashanth Sreenivasa <pks@delphix.com>
Reviewed by: Tim Chase <tim@chase2k.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
Author:     Serapheim Dimitropoulos <serapheim@delphix.com>
2018-08-02 23:56:07 +00:00
Alexander Motin
4d696665fd MFV r337206: 9338 moved dnode has incorrect dn_next_type
illumos/illumos-gate@c7fbe46df9

Reviewed by: Prashanth Sreenivasa <pks@delphix.com>
Reviewed by: Serapheim Dimitropoulos <serapheim.dimitro@delphix.com>
Reviewed by: Dan Kimmel <dan.kimmel@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author:     Matthew Ahrens <mahrens@delphix.com>
2018-08-02 23:50:03 +00:00
Alexander Motin
b9b2457429 MFV r337204: 9439 ZFS double-free due to failure to dirty indirect block
illumos/illumos-gate@99a19144e8

Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Paul Dagnelie <pcd@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author:     Matthew Ahrens <mahrens@delphix.com>
2018-08-02 23:46:30 +00:00
Alexander Motin
050b16aea8 MFV r337200:
9438 Holes can lose birth time info if a block has a mix of birth times

Ultimately, the problem here is that when you truncate and write a file in
the same transaction group, the dbuf for the indirect block will be zeroed
out to deal with the truncation, and then written for the write. During
this process, we will lose hole birth time information for any holes in the
range. In the case where a dnode is being freed, we need to determine
whether the block should be converted to a higher-level hole in the zio
pipeline, and if so do it when the dnode is being synced out.

illumos/illumos-gate@738e2a3ce3

Reviewed by: Matt Ahrens <matt@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author:     Paul Dagnelie <pcd@delphix.com>
2018-08-02 23:43:01 +00:00
Alexander Motin
7420e614fe Fix build after r337196 mismerge. 2018-08-02 23:40:28 +00:00
Alexander Motin
fc5b6d13a6 MFV r337197: 9456 ztest failure in zil_commit_waiter_timeout
illumos/illumos-gate@b6031810da

Reviewed by: Matt Ahrens <matt@delphix.com>
Reviewed by: Serapheim Dimitropoulos <serapheim.dimitro@delphix.com>
Approved by: Matt Ahrens <mahrens@delphix.com>
Author:     Prakash Surya <prakash.surya@delphix.com>
2018-08-02 23:25:49 +00:00
Alexander Motin
3a412471a4 MFV r337195: 9454 ::zfs_blkstats should count embedded blocks
illumos/illumos-gate@dec267e7ea

Reviewed by: Dan Kimmel <dan.kimmel@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author:     Matthew Ahrens <mahrens@delphix.com>
2018-08-02 23:23:10 +00:00
Alexander Motin
afc0e55ebb MFV r337193:
9424 ztest failure: "unprotected error in call to Lua API (Invalid value type 'f
unction' for key 'error')"

illumos/illumos-gate@fe3ba4d122

Reviewed by: Sebastien Roy <sebastien.roy@delphix.com>
Reviewed by: Paul Dagnelie <pcd@delphix.com>
Reviewed by: Don Brady <don.brady@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author:     Matthew Ahrens <mahrens@delphix.com>
2018-08-02 23:15:10 +00:00
Alexander Motin
01c0f8bef3 MFV r337190: 9486 reduce memory used by device removal on fragmented pools
In the most fragmented real-world cases, this reduces memory used by the
mapping from ~1GB to ~50MB of RAM per 1TB of storage removed. Less
fragmented cases will typically also see around 50-100MB of RAM per 1TB
of storage.

illumos/illumos-gate@cfd63e1b1b

Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Serapheim Dimitropoulos <serapheim.dimitro@delphix.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed by: Tim Chase <tim@chase2k.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author:     Matthew Ahrens <mahrens@delphix.com>
2018-08-02 21:59:46 +00:00
Alexander Motin
2bce9a5316 MFV r337182: 9330 stack overflow when creating a deeply nested dataset
Datasets that are deeply nested (~100 levels) are impractical. We just put
a limit of 50 levels to newly created datasets. Existing datasets should
work without a problem.

illumos/illumos-gate@5ac95da7d6

Reviewed by: John Kennedy <john.kennedy@delphix.com>
Reviewed by: Matt Ahrens <matt@delphix.com>
Approved by: Garrett D'Amore <garrett@damore.org>
Author:     Serapheim Dimitropoulos <serapheim.dimitro@delphix.com>
2018-08-02 21:19:35 +00:00
Alexander Motin
3f586250d8 9539 Make zvol operations use _by_dnode routines
Continues what was started in 7801 add more by-dnode routines by fully
converting zvols to avoid unnecessary dnode_hold() calls. This saves a
small amount of CPU time and slightly improves latencies of operations
on zvols.

illumos/illumos-gate@8dfe5547fb

Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed by: Rick McNeal <rick.mcneal@nexenta.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author:     Richard Yao <richard.yao@prophetstor.com>
2018-08-02 21:07:04 +00:00
Alexander Motin
5463ca24bf MFV r337175: 9487 Free objects when receiving full stream as clone
All objects after the last written or freed object are not supposed to
exist after receiving the stream. We should free them accordingly, as if
a freeobjects record for them had been included in the stream.

zfsonlinux/zfs@48fbb9ddbf
illumos/illumos-gate@7864b8192b

Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author:     Paul Dagnelie <pcd@delphix.com>
2018-08-02 20:33:13 +00:00
Alexander Motin
0485d5cba8 MFV r337171:
9464 txg_kick() fails to see that we are quiescing, forcing transactions
to their next stages without leaving them accumulate changes

Ideally we would like txg_kick() to get triggered only when we are sure
that we are not syncing AND not quiescing any txg. This way we can kick
an open TXG to the quiescing state when we are sure that there is nothing
going on and we would benefit from the different states running
concurrently.

illumos/illumos-gate@fa41d87de9

Reviewed by: Matt Ahrens <matt@delphix.com>
Reviewed by: Brad Lewis <brad.lewis@delphix.com>
Reviewed by: Andriy Gapon <avg@FreeBSD.org>
Approved by: Dan McDonald <danmcd@joyent.com>
Author:     Serapheim Dimitropoulos <serapheim@delphix.com>
2018-08-02 20:18:49 +00:00
Alexander Motin
aba9f1124f MFV r337167: 9442 decrease indirect block size of spacemaps
Updates to indirect blocks of spacemaps can contribute significantly to
write inflation.  Therefore we want to reduce the indirect block size of
spacemaps from 128K to 16K.

illumos/illumos-gate@221813c13b

Reviewed by: Serapheim Dimitropoulos <serapheim.dimitro@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Albert Lee <trisk@forkgnu.org>
Reviewed by: Igor Kozhukhov <igor@dilos.org>
Approved by: Dan McDonald <danmcd@joyent.com>
Author:     Matthew Ahrens <mahrens@delphix.com>
2018-08-02 20:06:46 +00:00