Implemented zpool scrub pause/resume

Currently, there is no way to pause a scrub. Pausing may
be useful when the pool is busy with other I/O to preserve
bandwidth.

This patch adds the ability to pause and resume scrubbing.
This is achieved by maintaining a persistent on-disk scrub state.
While the state is 'paused' we do not scrub any more blocks.
We do however perform regular scan housekeeping such as
freeing async destroyed and deadlist blocks while paused.

Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Thomas Caputi <tcaputi@datto.com>
Reviewed-by: Serapheim Dimitropoulos <serapheimd@gmail.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Alek Pinchuk <apinchuk@datto.com>
Closes #6167
This commit is contained in:
Alek P
2017-07-06 22:16:13 -07:00
committed by Brian Behlendorf
parent 94b25662c5
commit 0ea05c64f8
17 changed files with 364 additions and 126 deletions
+8
View File
@@ -24,6 +24,7 @@
* Copyright 2015 Nexenta Systems, Inc. All rights reserved.
* Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
* Copyright 2013 Saso Kiselkov. All rights reserved.
* Copyright (c) 2017 Datto Inc.
*/
#include <sys/zfs_context.h>
@@ -2007,6 +2008,11 @@ spa_scan_stat_init(spa_t *spa)
{
/* data not stored on disk */
spa->spa_scan_pass_start = gethrestime_sec();
if (dsl_scan_is_paused_scrub(spa->spa_dsl_pool->dp_scan))
spa->spa_scan_pass_scrub_pause = spa->spa_scan_pass_start;
else
spa->spa_scan_pass_scrub_pause = 0;
spa->spa_scan_pass_scrub_spent_paused = 0;
spa->spa_scan_pass_exam = 0;
vdev_scan_stat_init(spa->spa_root_vdev);
}
@@ -2037,6 +2043,8 @@ spa_scan_get_stats(spa_t *spa, pool_scan_stat_t *ps)
/* data not stored on disk */
ps->pss_pass_start = spa->spa_scan_pass_start;
ps->pss_pass_exam = spa->spa_scan_pass_exam;
ps->pss_pass_scrub_pause = spa->spa_scan_pass_scrub_pause;
ps->pss_pass_scrub_spent_paused = spa->spa_scan_pass_scrub_spent_paused;
return (0);
}