From 80a91e7469669e2a5da5873b8f09a752f7869062 Mon Sep 17 00:00:00 2001 From: Tom Caputi Date: Fri, 19 Oct 2018 00:06:18 -0400 Subject: Defer new resilvers until the current one ends Currently, if a resilver is triggered for any reason while an existing one is running, zfs will immediately restart the existing resilver from the beginning to include the new drive. This causes problems for system administrators when a drive fails while another is already resilvering. In this case, the optimal thing to do to reduce risk of data loss is to wait for the current resilver to end before immediately replacing the second failed drive, which allows the system to operate with two incomplete drives for the minimum amount of time. This patch introduces the resilver_defer feature that essentially does this for the admin without forcing them to wait and monitor the resilver manually. The change requires an on-disk feature since we must mark drives that are part of a deferred resilver in the vdev config to ensure that we do not assume they are done resilvering when an existing resilver completes. Reviewed-by: Matthew Ahrens Reviewed-by: John Kennedy Reviewed-by: Brian Behlendorf Reviewed-by: @mmaybee Signed-off-by: Tom Caputi Closes #7732 --- include/sys/fs/zfs.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/sys/fs') diff --git a/include/sys/fs/zfs.h b/include/sys/fs/zfs.h index 6bbf84346..4f0e13dfd 100644 --- a/include/sys/fs/zfs.h +++ b/include/sys/fs/zfs.h @@ -710,6 +710,7 @@ typedef struct zpool_load_policy { #define ZPOOL_CONFIG_VDEV_TOP_ZAP "com.delphix:vdev_zap_top" #define ZPOOL_CONFIG_VDEV_LEAF_ZAP "com.delphix:vdev_zap_leaf" #define ZPOOL_CONFIG_HAS_PER_VDEV_ZAPS "com.delphix:has_per_vdev_zaps" +#define ZPOOL_CONFIG_RESILVER_DEFER "com.datto:resilver_defer" #define ZPOOL_CONFIG_CACHEFILE "cachefile" /* not stored on disk */ #define ZPOOL_CONFIG_MMP_STATE "mmp_state" /* not stored on disk */ #define ZPOOL_CONFIG_MMP_TXG "mmp_txg" /* not stored on disk */ @@ -988,6 +989,7 @@ typedef struct vdev_stat { uint64_t vs_scan_processed; /* scan processed bytes */ uint64_t vs_fragmentation; /* device fragmentation */ uint64_t vs_checkpoint_space; /* checkpoint-consumed space */ + uint64_t vs_resilver_deferred; /* resilver deferred */ } vdev_stat_t; /* -- cgit v1.2.3