From b62e8d32da4e109b7e079d2d0b6c233dba0abcf0 Mon Sep 17 00:00:00 2001 From: Alexander Motin Date: Mon, 3 Jun 2019 19:53:39 +0000 Subject: [PATCH] 9963 Seperate tunable for disabling ZIL vdev flush illumos/illumos-gate@f8fdf6812567ce1a3b76a6bee2ee3f04bd3fcaca Reviewed by: Matt Ahrens Reviewed by: Brad Lewis Reviewed by: Patrick Mooney Approved by: Dan McDonald Author: Prakash Surya --- uts/common/fs/zfs/vdev_disk.c | 7 +++++++ uts/common/fs/zfs/zil.c | 13 +++++++------ 2 files changed, 14 insertions(+), 6 deletions(-) diff --git a/uts/common/fs/zfs/vdev_disk.c b/uts/common/fs/zfs/vdev_disk.c index 6adc387c882c..65d7864a526f 100644 --- a/uts/common/fs/zfs/vdev_disk.c +++ b/uts/common/fs/zfs/vdev_disk.c @@ -37,6 +37,13 @@ #include #include +/* + * Tunable parameter for debugging or performance analysis. Setting this + * will cause pool corruption on power loss if a volatile out-of-order + * write cache is enabled. + */ +boolean_t zfs_nocacheflush = B_FALSE; + /* * Virtual device vector for disks. */ diff --git a/uts/common/fs/zfs/zil.c b/uts/common/fs/zfs/zil.c index e365aad3c493..4909362e4e67 100644 --- a/uts/common/fs/zfs/zil.c +++ b/uts/common/fs/zfs/zil.c @@ -95,11 +95,12 @@ int zfs_commit_timeout_pct = 5; int zil_replay_disable = 0; /* - * Tunable parameter for debugging or performance analysis. Setting - * zfs_nocacheflush will cause corruption on power loss if a volatile - * out-of-order write cache is enabled. + * Disable the DKIOCFLUSHWRITECACHE commands that are normally sent to + * the disk(s) by the ZIL after an LWB write has completed. Setting this + * will cause ZIL corruption on power loss if a volatile out-of-order + * write cache is enabled. */ -boolean_t zfs_nocacheflush = B_FALSE; +boolean_t zil_nocacheflush = B_FALSE; /* * Limit SLOG write size per commit executed with synchronous priority. @@ -991,7 +992,7 @@ zil_lwb_add_block(lwb_t *lwb, const blkptr_t *bp) int ndvas = BP_GET_NDVAS(bp); int i; - if (zfs_nocacheflush) + if (zil_nocacheflush) return; mutex_enter(&lwb->lwb_vdev_lock); @@ -1015,7 +1016,7 @@ zil_lwb_add_txg(lwb_t *lwb, uint64_t txg) /* * This function is a called after all VDEVs associated with a given lwb * write have completed their DKIOCFLUSHWRITECACHE command; or as soon - * as the lwb write completes, if "zfs_nocacheflush" is set. + * as the lwb write completes, if "zil_nocacheflush" is set. * * The intention is for this function to be called as soon as the * contents of an lwb are considered "stable" on disk, and will survive