Brian Behlendorf 9c1a8eaa51 Fix ARC hit rate ... When the compressed ARC feature was added in commit d3c2ae1 the method of reference counting in the ARC was modified. As part of this accounting change the arc_buf_add_ref() function was removed entirely. This would have be fine but the arc_buf_add_ref() function served a second undocumented purpose of updating the ARC access information when taking a hold on a dbuf. Without this logic in place a cached dbuf would not migrate its associated arc_buf_hdr_t to the MFU list. This would negatively impact the ARC hit rate, particularly on systems with a small ARC. This change reinstates the missing call to arc_access() from dbuf_hold() by implementing a new arc_buf_access() function. Reviewed-by: Giuseppe Di Natale <dinatale2@llnl.gov> Reviewed-by: Tony Hutter <hutter2@llnl.gov> Reviewed-by: Tim Chase <tim@chase2k.com> Reviewed by: George Wilson <george.wilson@delphix.com> Reviewed-by: George Melikov <mail@gmelikov.ru> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Closes #6171 Closes #6852 Closes #6989		2018-01-30 10:27:31 -06:00
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linux	Linux 4.14 compat: IO acct, global_page_state, etc (#6655)	2017-09-19 14:24:34 -07:00
sys	Fix ARC hit rate	2018-01-30 10:27:31 -06:00
libnvpair.h	Support custom build directories and move includes	2010-09-08 12:38:56 -07:00
libuutil_common.h	Support custom build directories and move includes	2010-09-08 12:38:56 -07:00
libuutil_impl.h	Support custom build directories and move includes	2010-09-08 12:38:56 -07:00
libuutil.h	Correct cppcheck errors (#6662)	2017-09-20 12:59:21 -07:00
libzfs_core.h	OpenZFS 7600 - zfs rollback should pass target snapshot to kernel	2017-07-04 15:29:52 -07:00
libzfs_impl.h	Multi-modifier protection (MMP)	2017-07-13 13:54:00 -04:00
libzfs.h	Multi-modifier protection (MMP)	2017-07-13 13:54:00 -04:00
Makefile.am	Kernel header installation should respect --prefix	2014-10-28 09:37:06 -07:00
zfeature_common.h	OpenZFS 2932 - support crash dumps to raidz, etc. pools	2017-04-10 10:24:17 -07:00
zfs_comutil.h	Illumos #2882, #2883, #2900	2013-09-04 15:49:00 -07:00
zfs_deleg.h	Add support for user/group dnode accounting & quota	2016-10-07 09:45:13 -07:00
zfs_fletcher.h	DLPX-44812 integrate EP-220 large memory scalability	2016-11-29 14:34:27 -08:00
zfs_namecheck.h	OpenZFS 7386 - zfs get does not work properly with bookmarks	2017-01-26 14:42:15 -08:00
zfs_prop.h	Check the dataset type more rigorously when fetching properties.	2014-05-06 10:41:46 -07:00
zpios-ctl.h	Fix spelling	2017-01-03 11:31:18 -06:00
zpios-internal.h	Fix spelling	2017-01-03 11:31:18 -06:00