freebsd-nq/include/sys/dsl_deadlist.h
Matthew Ahrens 325d288c5d Add fast path for zfs_ioc_space_snaps() handling of empty_bpobj
When there are many snapshots, calls to zfs_ioc_space_snaps() (e.g. from
`zfs destroy -nv pool/fs@snap1%snap10000`) can be very slow, resulting
in poor performance because we are holding the dp_config_rwlock the
entire time, blocking spa_sync() from continuing.  With around ten
thousand snapshots, we've seen up to 500 seconds in this ioctl,
iterating over up to 50,000,000 bpobjs, ~99% of which are the empty
bpobj.

By creating a fast path for zfs_ioc_space_snaps() handling of the
empty_bpobj, we can achieve a ~5x performance improvement of this ioctl
(when there are many snapshots, and the deadlist is mostly
empty_bpobj's).

Reviewed-by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
External-issue: DLPX-58348
Closes #8744
2019-08-20 11:34:52 -07:00

129 lines
4.2 KiB
C

/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2018, 2019 by Delphix. All rights reserved.
*/
#ifndef _SYS_DSL_DEADLIST_H
#define _SYS_DSL_DEADLIST_H
#include <sys/bpobj.h>
#include <sys/zfs_context.h>
#include <sys/zthr.h>
#ifdef __cplusplus
extern "C" {
#endif
struct dmu_buf;
struct dsl_pool;
struct dsl_dataset;
typedef struct dsl_deadlist_phys {
uint64_t dl_used;
uint64_t dl_comp;
uint64_t dl_uncomp;
uint64_t dl_pad[37]; /* pad out to 320b for future expansion */
} dsl_deadlist_phys_t;
typedef struct dsl_deadlist {
objset_t *dl_os;
uint64_t dl_object;
avl_tree_t dl_tree; /* contains dsl_deadlist_entry_t */
avl_tree_t dl_cache; /* contains dsl_deadlist_cache_entry_t */
boolean_t dl_havetree;
boolean_t dl_havecache;
struct dmu_buf *dl_dbuf;
dsl_deadlist_phys_t *dl_phys;
kmutex_t dl_lock;
/* if it's the old on-disk format: */
bpobj_t dl_bpobj;
boolean_t dl_oldfmt;
} dsl_deadlist_t;
typedef struct dsl_deadlist_cache_entry {
avl_node_t dlce_node;
uint64_t dlce_mintxg;
uint64_t dlce_bpobj;
uint64_t dlce_bytes;
uint64_t dlce_comp;
uint64_t dlce_uncomp;
} dsl_deadlist_cache_entry_t;
typedef struct dsl_deadlist_entry {
avl_node_t dle_node;
uint64_t dle_mintxg;
bpobj_t dle_bpobj;
} dsl_deadlist_entry_t;
typedef struct livelist_condense_entry {
struct dsl_dataset *ds;
dsl_deadlist_entry_t *first;
dsl_deadlist_entry_t *next;
boolean_t syncing;
boolean_t cancelled;
} livelist_condense_entry_t;
extern unsigned long zfs_livelist_max_entries;
extern int zfs_livelist_min_percent_shared;
typedef int deadlist_iter_t(void *args, dsl_deadlist_entry_t *dle);
void dsl_deadlist_open(dsl_deadlist_t *dl, objset_t *os, uint64_t object);
void dsl_deadlist_close(dsl_deadlist_t *dl);
void dsl_deadlist_iterate(dsl_deadlist_t *dl, deadlist_iter_t func, void *arg);
uint64_t dsl_deadlist_alloc(objset_t *os, dmu_tx_t *tx);
void dsl_deadlist_free(objset_t *os, uint64_t dlobj, dmu_tx_t *tx);
void dsl_deadlist_insert(dsl_deadlist_t *dl, const blkptr_t *bp,
boolean_t free, dmu_tx_t *tx);
int dsl_deadlist_insert_alloc_cb(void *arg, const blkptr_t *bp, dmu_tx_t *tx);
int dsl_deadlist_insert_free_cb(void *arg, const blkptr_t *bp, dmu_tx_t *tx);
void dsl_deadlist_add_key(dsl_deadlist_t *dl, uint64_t mintxg, dmu_tx_t *tx);
void dsl_deadlist_remove_key(dsl_deadlist_t *dl, uint64_t mintxg, dmu_tx_t *tx);
void dsl_deadlist_remove_entry(dsl_deadlist_t *dl, uint64_t mintxg,
dmu_tx_t *tx);
dsl_deadlist_entry_t *dsl_deadlist_first(dsl_deadlist_t *dl);
dsl_deadlist_entry_t *dsl_deadlist_last(dsl_deadlist_t *dl);
uint64_t dsl_deadlist_clone(dsl_deadlist_t *dl, uint64_t maxtxg,
uint64_t mrs_obj, dmu_tx_t *tx);
void dsl_deadlist_space(dsl_deadlist_t *dl,
uint64_t *usedp, uint64_t *compp, uint64_t *uncompp);
void dsl_deadlist_space_range(dsl_deadlist_t *dl,
uint64_t mintxg, uint64_t maxtxg,
uint64_t *usedp, uint64_t *compp, uint64_t *uncompp);
void dsl_deadlist_merge(dsl_deadlist_t *dl, uint64_t obj, dmu_tx_t *tx);
void dsl_deadlist_move_bpobj(dsl_deadlist_t *dl, bpobj_t *bpo, uint64_t mintxg,
dmu_tx_t *tx);
boolean_t dsl_deadlist_is_open(dsl_deadlist_t *dl);
int dsl_process_sub_livelist(bpobj_t *bpobj, struct bplist *to_free,
zthr_t *t, uint64_t *size);
void dsl_deadlist_clear_entry(dsl_deadlist_entry_t *dle, dsl_deadlist_t *dl,
dmu_tx_t *tx);
void dsl_deadlist_discard_tree(dsl_deadlist_t *dl);
#ifdef __cplusplus
}
#endif
#endif /* _SYS_DSL_DEADLIST_H */