mirror_zfs/module
Paul Dagnelie f664f1ee7f Decrease contention on dn_struct_rwlock
Currently, sequential async write workloads spend a lot of time 
contending on the dn_struct_rwlock. This lock is responsible for 
protecting the entire block tree below it; this naturally results 
in some serialization during heavy write workloads. This can be 
resolved by having per-dbuf locking, which will allow multiple 
writers in the same object at the same time.

We introduce a new rwlock, the db_rwlock. This lock is responsible 
for protecting the contents of the dbuf that it is a part of; when 
reading a block pointer from a dbuf, you hold the lock as a reader. 
When writing data to a dbuf, you hold it as a writer. This allows 
multiple threads to write to different parts of a file at the same 
time.

Reviewed by: Brad Lewis <brad.lewis@delphix.com>
Reviewed by: Matt Ahrens matt@delphix.com
Reviewed by: George Wilson george.wilson@delphix.com
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
External-issue: DLPX-52564
External-issue: DLPX-53085
External-issue: DLPX-57384
Closes #8946
2019-07-08 13:18:50 -07:00
..
avl Update build system and packaging 2018-05-29 16:00:33 -07:00
icp Restructure vec_idx loops 2019-04-16 12:34:06 -07:00
lua Update build system and packaging 2018-05-29 16:00:33 -07:00
nvpair Use NV_ENCODE_NATIVE for nvlist encoding variable 2019-04-26 11:24:31 -07:00
spl OpenZFS 9425 - channel programs can be interrupted 2019-06-22 16:51:46 -07:00
unicode Update build system and packaging 2018-05-29 16:00:33 -07:00
zcommon Remove code for zfs remap 2019-06-24 16:44:01 -07:00
zfs Decrease contention on dn_struct_rwlock 2019-07-08 13:18:50 -07:00
.gitignore Prepare SPL repo to merge with ZFS repo 2018-05-29 14:51:39 -07:00
Makefile.in Fix out-of-tree build failures 2019-06-24 09:32:47 -07:00