c/mirror_zfs
1
0
Fork 0
mirror of https://git.proxmox.com/git/mirror_zfs.git synced 2026-05-25 03:37:45 +03:00
Code Issues Packages Projects Releases Wiki Activity

OpenZFS 7968 - multi-threaded spa_sync()

Browse Source 
Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed by: Brad Lewis <brad.lewis@delphix.com>
Reviewed by: Saso Kiselkov <saso.kiselkov@nexenta.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Ported-by: Matthew Ahrens <mahrens@delphix.com>

spa_sync() iterates over all the dirty dnodes and processes each of them
by calling dnode_sync(). If there are many dirty dnodes (e.g. because we
created or removed a lot of files), the single thread of spa_sync()
calling dnode_sync() can become a bottleneck. Additionally, if many
dnodes are dirtied concurrently in open context (e.g. due to concurrent
file creation), the os_lock will experience lock contention via
dnode_setdirty().

The solution is to track dirty dnodes on a multilist_t, and for
spa_sync() to use separate threads to process each of the sublists in
the multilist.

OpenZFS-issue: https://www.illumos.org/issues/7968
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/4a2a54c
Closes #5752
This commit is contained in:
Matthew Ahrens
2017-03-20 18:36:00 -07:00
committed by Brian Behlendorf
parent a3478c0747
commit 64fc776208
16 changed files with 303 additions and 159 deletions
Download Patch File Download Diff File Expand all files Collapse all files
module/zfs/dnode.c
+7 -29
View File
@@ -20,7 +20,7 @@
*/
/*
* Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2012, 2016 by Delphix. All rights reserved.
* Copyright (c) 2012, 2017 by Delphix. All rights reserved.
* Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
*/
@@ -1421,13 +1421,14 @@ dnode_setdirty(dnode_t *dn, dmu_tx_t *tx)
*/
dmu_objset_userquota_get_ids(dn, B_TRUE, tx);
mutex_enter(&os->os_lock);
multilist_t *dirtylist = os->os_dirty_dnodes[txg & TXG_MASK];
multilist_sublist_t *mls = multilist_sublist_lock_obj(dirtylist, dn);
/*
* If we are already marked dirty, we're done.
*/
if (list_link_active(&dn->dn_dirty_link[txg & TXG_MASK])) {
mutex_exit(&os->os_lock);
multilist_sublist_unlock(mls);
return;
}
@@ -1441,13 +1442,9 @@ dnode_setdirty(dnode_t *dn, dmu_tx_t *tx)
dprintf_ds(os->os_dsl_dataset, "obj=%llu txg=%llu\n",
dn->dn_object, txg);
if (dn->dn_free_txg > 0 && dn->dn_free_txg <= txg) {
list_insert_tail(&os->os_free_dnodes[txg&TXG_MASK], dn);
} else {
list_insert_tail(&os->os_dirty_dnodes[txg&TXG_MASK], dn);
}
multilist_sublist_insert_head(mls, dn);
mutex_exit(&os->os_lock);
multilist_sublist_unlock(mls);
/*
* The dnode maintains a hold on its containing dbuf as
@@ -1468,13 +1465,6 @@ dnode_setdirty(dnode_t *dn, dmu_tx_t *tx)
void
dnode_free(dnode_t *dn, dmu_tx_t *tx)
{
int txgoff = tx->tx_txg & TXG_MASK;
dprintf("dn=%p txg=%llu\n", dn, tx->tx_txg);
/* we should be the only holder... hopefully */
/* ASSERT3U(refcount_count(&dn->dn_holds), ==, 1); */
mutex_enter(&dn->dn_mtx);
if (dn->dn_type == DMU_OT_NONE || dn->dn_free_txg) {
mutex_exit(&dn->dn_mtx);
@@ -1483,19 +1473,7 @@ dnode_free(dnode_t *dn, dmu_tx_t *tx)
dn->dn_free_txg = tx->tx_txg;
mutex_exit(&dn->dn_mtx);
/*
* If the dnode is already dirty, it needs to be moved from
* the dirty list to the free list.
*/
mutex_enter(&dn->dn_objset->os_lock);
if (list_link_active(&dn->dn_dirty_link[txgoff])) {
list_remove(&dn->dn_objset->os_dirty_dnodes[txgoff], dn);
list_insert_tail(&dn->dn_objset->os_free_dnodes[txgoff], dn);
mutex_exit(&dn->dn_objset->os_lock);
} else {
mutex_exit(&dn->dn_objset->os_lock);
dnode_setdirty(dn, tx);
}
dnode_setdirty(dn, tx);
}
/*