OpenZFS 7968 - multi-threaded spa_sync()

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
+2 -2
View File
@@ -22,7 +22,7 @@
/*
* Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
* Copyright 2011 Nexenta Systems, Inc. All rights reserved.
* Copyright (c) 2012, 2016 by Delphix. All rights reserved.
* Copyright (c) 2012, 2017 by Delphix. All rights reserved.
* Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
*/
@@ -454,7 +454,7 @@ struct zio {
taskq_ent_t io_tqent;
};
extern int zio_timestamp_compare(const void *, const void *);
extern int zio_bookmark_compare(const void *, const void *);
extern zio_t *zio_null(zio_t *pio, spa_t *spa, vdev_t *vd,
zio_done_func_t *done, void *private, enum zio_flag flags);