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Andriy Gapon 1c42c71f38 8025 dbuf_read() creates unnecessary zio_root() for bonus buf ... illumos/illumos-gate@def4fac588 def4fac588 https://www.illumos.org/issues/8025 dbuf_read() creates a zio_root() to track and wait for all the zio's that may happen as part of this call. However, if the blkptr_t for this buffer is NULL or a hole, we will not create any more zio's, so this zio_root() is unnecessary. This is always the case when calling dbuf_read() on a bonus buffer, because it has no blkptr (it's part of the containing dnode). For workloads that read a lot of bonus buffers (e.g. file creation and removal), creating and destroying these unnecessary zio's can decrease performance by around 3%. Reviewed by: Dan Kimmel <dan.kimmel@delphix.com> Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com> Reviewed by: Prashanth Sreenivasa <pks@delphix.com> Approved by: Robert Mustacchi <rm@joyent.com> Author: Matthew Ahrens <mahrens@delphix.com>		2017-05-26 11:29:31 +00:00
cmd	7955 libshare needs to initialize only those datasets being modified by the consumer	2017-04-14 18:34:03 +00:00
common	7812 Remove gender specific language	2017-04-14 18:22:42 +00:00
head	5066 remove support for non-ANSI compilation	2014-08-20 06:29:42 +00:00
lib	5704 libzfs can only handle 255 file descriptors	2017-04-14 18:56:00 +00:00
man	7252 7628 compressed zfs send / receive	2017-04-14 18:07:43 +00:00
tools/ctf	5589 improper use of NULL in tools/ctf	2015-03-09 20:43:14 +00:00
uts	8025 dbuf_read() creates unnecessary zio_root() for bonus buf	2017-05-26 11:29:31 +00:00
OPENSOLARIS.LICENSE	Update vendor/opensolaris to last OpenSolaris state (13149:b23a4dab3d50)	2012-07-18 07:48:04 +00:00