Andriy Gapon 0c4f60b734 MFV r353619: 9691 fat zap should prefetch when iterating ... illumos/illumos-gate@52abb70e07 52abb70e07 https://www.illumos.org/issues/9691 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. Author: Matthew Ahrens <mahrens@delphix.com> Obtained from: illumos MFC after: 2 weeks		2019-10-16 07:09:00 +00:00
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boot/zfs	loader: support com.delphix:removing	2019-08-08 18:08:13 +00:00
compat/opensolaris	fix up r353340, don't assume that fcmpset has strong semantics	2019-10-11 17:01:02 +00:00
contrib/opensolaris	MFV r353619: 9691 fat zap should prefetch when iterating	2019-10-16 07:09:00 +00:00
dev	dtrace: 64-bits registers support	2019-10-04 16:17:00 +00:00