mirror_zfs/tests/zfs-tests/tests/functional/replacement
Paul Dagnelie d64711c202 Detect a slow raidz child during reads
A single slow responding disk can affect the overall read
performance of a raidz group.  When a raidz child disk is
determined to be a persistent slow outlier, then have it
sit out during reads for a period of time. The raidz group
can use parity to reconstruct the data that was skipped.

Each time a slow disk is placed into a sit out period, its
`vdev_stat.vs_slow_ios count` is incremented and a zevent
class `ereport.fs.zfs.delay` is posted.

The length of the sit out period can be changed using the
`raid_read_sit_out_secs` module parameter.  Setting it to
zero disables slow outlier detection.

Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Paul Dagnelie <paul.dagnelie@klarasystems.com>
Contributions-by: Don Brady <don.brady@klarasystems.com>
Contributions-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #17227
2025-09-10 15:25:03 -07:00
..
attach_import.ksh SPDX: license tags: CDDL-1.0 2025-03-13 17:56:27 -07:00
attach_multiple.ksh SPDX: license tags: CDDL-1.0 2025-03-13 17:56:27 -07:00
attach_rebuild.ksh SPDX: license tags: CDDL-1.0 2025-03-13 17:56:27 -07:00
attach_resilver_sit_out.ksh Detect a slow raidz child during reads 2025-09-10 15:25:03 -07:00
attach_resilver.ksh SPDX: license tags: CDDL-1.0 2025-03-13 17:56:27 -07:00
cleanup.ksh SPDX: license tags: CDDL-1.0 2025-03-13 17:56:27 -07:00
detach.ksh SPDX: license tags: CDDL-1.0 2025-03-13 17:56:27 -07:00
rebuild_disabled_feature.ksh SPDX: license tags: CDDL-1.0 2025-03-13 17:56:27 -07:00
rebuild_multiple.ksh SPDX: license tags: CDDL-1.0 2025-03-13 17:56:27 -07:00
rebuild_raidz.ksh SPDX: license tags: CDDL-1.0 2025-03-13 17:56:27 -07:00
replace_import.ksh SPDX: license tags: CDDL-1.0 2025-03-13 17:56:27 -07:00
replace_rebuild.ksh SPDX: license tags: CDDL-1.0 2025-03-13 17:56:27 -07:00
replace_resilver_sit_out.ksh Detect a slow raidz child during reads 2025-09-10 15:25:03 -07:00
replace_resilver.ksh SPDX: license tags: CDDL-1.0 2025-03-13 17:56:27 -07:00
replacement.cfg SPDX: license tags: CDDL-1.0 2025-03-13 17:56:27 -07:00
resilver_restart_001.ksh ZTS: Fix replacement/resilver_restart_001 on FreeBSD 2025-05-02 12:02:14 -04:00
resilver_restart_002.ksh SPDX: license tags: CDDL-1.0 2025-03-13 17:56:27 -07:00
scrub_cancel.ksh SPDX: license tags: CDDL-1.0 2025-03-13 17:56:27 -07:00
setup.ksh SPDX: license tags: CDDL-1.0 2025-03-13 17:56:27 -07:00