jpaetzel 4c97ff8bf5 MFV 316895 ... 7606 dmu_objset_find_dp() takes a long time while importing pool illumos/illumos-gate@7588687e6b 7588687e6b https://www.illumos.org/issues/7606 When importing a pool with a large number of filesystems within the same parent filesystem, we see that dmu_objset_find_dp() takes a long time. It is called from 3 places: spa_check_logs(), spa_ld_claim_log_blocks(), and spa_load_verify(). There are several ways to improve performance here: 1. We don't really need to do spa_check_logs() or spa_ld_claim_log_blocks() if the pool was closed cleanly. 2. spa_load_verify() uses dmu_objset_find_dp() to check that no datasets have too long of names. 3. dmu_objset_find_dp() is slow because it's doing zap_value_search() (which is O(N sibling datasets)) to determine the name of each dsl_dir when it's opened. In this case we actually know the name when we are opening it, so we can provide it and avoid the lookup. This change implements fix #3 from the above list; i.e. make dmu_objset_find_dp() provide the name of the dataset so that we don't have to search for it. Reviewed by: Steve Gonczi <steve.gonczi@delphix.com> Reviewed by: George Wilson <george.wilson@delphix.com> Reviewed by: Prashanth Sreenivasa <prashksp@gmail.com> Approved by: Gordon Ross <gordon.w.ross@gmail.com> Author: Matthew Ahrens <mahrens@delphix.com>		2017-04-27 15:10:45 +00:00
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boot/zfs	loader: update symlink support in zfs reader	2017-02-22 22:00:50 +00:00
compat/opensolaris	All these files need sys/vmmeter.h, but now they got it implicitly	2017-04-17 17:07:00 +00:00
contrib/opensolaris	MFV 316895	2017-04-27 15:10:45 +00:00
dev	Corrected misspelled versions of rendezvous.	2017-04-09 02:00:03 +00:00