Matthew Ahrens d9b4bf0665 fat zap should prefetch when iterating ... When iterating over a ZAP object, we're almost always certain to iterate over the entire object. If there are multiple leaf blocks, we can realize a performance win by issuing reads for all the leaf blocks in parallel when the iteration begins. For example, if we have 10,000 snapshots, "zfs destroy -nv pool/fs@1%9999" can take 30 minutes when the cache is cold. This change provides a >3x performance improvement, by issuing the reads for all ~64 blocks of each ZAP object in parallel. Reviewed-by: Andreas Dilger <andreas.dilger@whamcloud.com> Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Matthew Ahrens <mahrens@delphix.com> External-issue: DLPX-58347 Closes #8862		2019-06-12 13:13:09 -07:00
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Makefile.am	Update build system and packaging	2018-05-29 16:00:33 -07:00
spl-module-parameters.5	Update spl module parameters man5 with missing parameter details	2017-10-27 15:46:34 -07:00
vdev_id.conf.5	Add enclosure_symlinks option to vdev_id	2018-12-14 17:27:49 -08:00
zfs-events.5	Add zpool status -s (slow I/Os) and -p (parseable)	2018-11-08 16:47:24 -08:00
zfs-module-parameters.5	fat zap should prefetch when iterating	2019-06-12 13:13:09 -07:00
zpool-features.5	Eliminate useless double-bolding in man pages	2019-04-24 17:04:35 -07:00