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NEX-5367 special vdev: sync-write options (NEW)
Reviewed by: Roman Strashkin <roman.strashkin@nexenta.com>
Reviewed by: Alek Pinchuk <alek.pinchuk@nexenta.com>
NEX-4794 Write Back Cache sync and async writes: adjust routing according to watermark limits
Reviewed by: Alex Aizman <alex.aizman@nexenta.com>
Reviewed by: Alek Pinchuk <alek.pinchuk@nexenta.com>
6328 Fix cstyle errors in zfs codebase (fix studio)
6328 Fix cstyle errors in zfs codebase
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Alex Reece <alex@delphix.com>
Reviewed by: Richard Elling <Richard.Elling@RichardElling.com>
Reviewed by: Jorgen Lundman <lundman@lundman.net>
Approved by: Robert Mustacchi <rm@joyent.com>
Issues #7: Reconsile L2ARC and "special" use by datasets
re #12616 rb4051 zfs_log_write()/dmu_sync() write once to special refactoring
re #12585 rb4049 ZFS++ work port - refactoring to improve separation of open/closed code, bug fixes, performance improvements - open code
*** 18,27 ****
--- 18,28 ----
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright 2013 Nexenta Systems, Inc. All rights reserved.
* Copyright (c) 2015 by Delphix. All rights reserved.
* Copyright (c) 2014 Integros [integros.com]
*/
#include <sys/types.h>
*** 42,54 ****
--- 43,57 ----
#include <sys/stat.h>
#include <sys/mode.h>
#include <sys/acl.h>
#include <sys/dmu.h>
#include <sys/spa.h>
+ #include <sys/spa_impl.h>
#include <sys/zfs_fuid.h>
#include <sys/ddi.h>
#include <sys/dsl_dataset.h>
+ #include <sys/special.h>
/*
* These zfs_log_* functions must be called within a dmu tx, in one
* of 2 contexts depending on zilog->z_replay:
*
*** 452,478 ****
void
zfs_log_write(zilog_t *zilog, dmu_tx_t *tx, int txtype,
znode_t *zp, offset_t off, ssize_t resid, int ioflag)
{
! uint32_t blocksize = zp->z_blksz;
itx_wr_state_t write_state;
uintptr_t fsync_cnt;
if (zil_replaying(zilog, tx) || zp->z_unlinked)
return;
! if (zilog->zl_logbias == ZFS_LOGBIAS_THROUGHPUT)
write_state = WR_INDIRECT;
else if (!spa_has_slogs(zilog->zl_spa) &&
resid >= zfs_immediate_write_sz)
write_state = WR_INDIRECT;
else if (ioflag & (FSYNC | FDSYNC))
write_state = WR_COPIED;
else
write_state = WR_NEED_COPY;
if ((fsync_cnt = (uintptr_t)tsd_get(zfs_fsyncer_key)) != 0) {
(void) tsd_set(zfs_fsyncer_key, (void *)(fsync_cnt - 1));
}
while (resid) {
--- 455,545 ----
void
zfs_log_write(zilog_t *zilog, dmu_tx_t *tx, int txtype,
znode_t *zp, offset_t off, ssize_t resid, int ioflag)
{
! spa_t *spa = zilog->zl_spa;
! spa_meta_placement_t *mp = &spa->spa_meta_policy;
itx_wr_state_t write_state;
+ boolean_t slogging, zil_to_special, write_to_special;
+ size_t immediate_write_sz;
+ uint32_t blocksize = zp->z_blksz;
uintptr_t fsync_cnt;
if (zil_replaying(zilog, tx) || zp->z_unlinked)
return;
! /*
! * Decide how to handle the write:
! * - WR_INDIRECT - synchronously write in zfs format, via dmu_sync()
! * - WR_COPIED - write to slog following the tx descriptor as
! * immediate data
! * - WR_NEED_COPY - copy out in the future (e.g. with next sync)
! *
! * Special vdevs are as fast as slogs - therefore a conservative
! * extension to the existing logic allows for the following
! * zpool-configurable options:
! *
! * (1) SYNC_TO_SPECIAL_DISABLED: do not use special vdev,
! * neither for zil, nor for WR_INDIRECT
! * (2) SYNC_TO_SPECIAL_STANDARD (default): use special vdev
! * exactly like slog
! * The remaining two options add the capability to sync data to
! * special vdev:
! * (3) SYNC_TO_SPECIAL_BALANCED: same as "standard", plus
! * load balance writes to the special vdev
! * (4) SYNC_TO_SPECIAL_ALWAYS: same as "standard" plus always
! * write to the special vdev
! *
! * Presence of special vdev has no affect if slog is configured:
! * the latter indicates that user expects conventional zfs
! * sync-write behavior.
! */
!
! immediate_write_sz = (zilog->zl_logbias == ZFS_LOGBIAS_THROUGHPUT)
! ? 0 : zfs_immediate_write_sz;
!
! /* use special only if all of the following is true */
! zil_to_special = !spa_has_slogs(spa) &&
! spa_can_special_be_used(spa) &&
! mp->spa_sync_to_special != SYNC_TO_SPECIAL_DISABLED;
!
! /*
! * synchronously write data to special in zfs format - the
! * WR_INDIRECT case
! *
! * for the "balanced" option distribute the load based on the
! * special-to-normal ratio - the value that is periodically
! * recomputed by the load balancer implementing one of
! * SPA_SPECIAL_SELECTION_LATENCY etc. strategies
! */
! write_to_special = !spa_has_slogs(spa) &&
! spa_write_data_to_special(spa, zilog->zl_os) &&
! (mp->spa_sync_to_special == SYNC_TO_SPECIAL_ALWAYS ||
! (mp->spa_sync_to_special == SYNC_TO_SPECIAL_BALANCED &&
! spa->spa_avg_stat_rotor % 100 < spa->spa_special_to_normal_ratio));
!
! slogging = (spa_has_slogs(spa) || zil_to_special) &&
! zilog->zl_logbias == ZFS_LOGBIAS_LATENCY;
!
! if (resid > immediate_write_sz && !slogging && resid <= blocksize)
write_state = WR_INDIRECT;
+ else if (zilog->zl_logbias == ZFS_LOGBIAS_THROUGHPUT)
+ write_state = WR_INDIRECT;
else if (!spa_has_slogs(zilog->zl_spa) &&
resid >= zfs_immediate_write_sz)
write_state = WR_INDIRECT;
+ else if (write_to_special)
+ write_state = WR_INDIRECT;
else if (ioflag & (FSYNC | FDSYNC))
write_state = WR_COPIED;
else
write_state = WR_NEED_COPY;
+ DTRACE_PROBE3(zfs_lwr, ssize_t, immediate_write_sz,
+ itx_wr_state_t, write_state, uint_t, zp->z_blksz);
+
if ((fsync_cnt = (uintptr_t)tsd_get(zfs_fsyncer_key)) != 0) {
(void) tsd_set(zfs_fsyncer_key, (void *)(fsync_cnt - 1));
}
while (resid) {