linux_dsm_epyc7002/drivers/md/bcache
Tang Junhui 89b1fc54c2 bcache: increase the number of open buckets
In currently, we only alloc 6 open buckets for each cache set,
but in usually, we always attach about 10 or so backend devices for
each cache set, and the each bcache device are always accessed by
about 10 or so threads in top application layer. So 6 open buckets
are too few, It has led to that each of the same thread write data
to different buckets, which would cause low efficiency write-back,
and also cause buckets inefficient, and would be Very easy to run
out of.

I add debug message in bch_open_buckets_alloc() to print alloc bucket
info, and test with ten bcache devices with a cache set, and each
bcache device is accessed by ten threads.

From the debug message, we can see that, after the modification, One
bucket is more likely to assign to the same thread, and the data from
the same thread are more likely to write the same bucket. Usually the
same thread always write/read the same backend device, so it is good
for write-back and also promote the usage efficiency of buckets.

Signed-off-by: Tang Junhui <tang.junhui@zte.com.cn>
Reviewed-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-09-06 08:17:33 -06:00
..
alloc.c bcache: increase the number of open buckets 2017-09-06 08:17:33 -06:00
bcache.h block: switch bios to blk_status_t 2017-06-09 09:27:32 -06:00
bset.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/clock.h> 2017-03-02 08:42:27 +01:00
bset.h bcache: fix typo in bch_bkey_equal_header 2014-08-04 15:23:03 -07:00
btree.c block: switch bios to blk_status_t 2017-06-09 09:27:32 -06:00
btree.h sched/wait: Rename wait_queue_t => wait_queue_entry_t 2017-06-20 12:18:27 +02:00
closure.c bcache: Don't reinvent the wheel but use existing llist API 2017-09-06 08:17:33 -06:00
closure.h sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h> 2017-03-02 08:42:36 +01:00
debug.c block: replace bi_bdev with a gendisk pointer and partitions index 2017-08-23 12:49:55 -06:00
debug.h bcache: Convert debug code to btree_keys 2014-01-08 13:05:13 -08:00
extents.c bcache: Fix a journal replay bug 2014-08-04 15:23:02 -07:00
extents.h bcache: Fix a journal replay bug 2014-08-04 15:23:02 -07:00
io.c block: replace bi_bdev with a gendisk pointer and partitions index 2017-08-23 12:49:55 -06:00
journal.c block: replace bi_bdev with a gendisk pointer and partitions index 2017-08-23 12:49:55 -06:00
journal.h bcache: Fix a shutdown bug 2014-02-25 18:42:49 -08:00
Kconfig bcache: Kill dead cgroup code 2014-03-18 12:22:35 -07:00
Makefile bcache: Abstract out stuff needed for sorting 2014-01-08 13:05:12 -08:00
movinggc.c block: switch bios to blk_status_t 2017-06-09 09:27:32 -06:00
request.c bcache: do not subtract sectors_to_gc for bypassed IO 2017-09-06 08:17:33 -06:00
request.h block: switch bios to blk_status_t 2017-06-09 09:27:32 -06:00
stats.c bcache: Kill dead cgroup code 2014-03-18 12:22:35 -07:00
stats.h bcache: Break up struct search 2013-11-10 21:56:32 -08:00
super.c bcache: Fix leak of bdev reference 2017-09-06 08:17:33 -06:00
sysfs.c bcache: Correct return value for sysfs attach errors 2017-09-06 08:17:33 -06:00
sysfs.h bcache: Don't export utility code, prefix with bch_ 2013-03-28 12:50:55 -06:00
trace.c bcache: Better alloc tracepoints 2014-03-18 12:22:35 -07:00
util.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/clock.h> 2017-03-02 08:42:27 +01:00
util.h treewide: use kv[mz]alloc* rather than opencoded variants 2017-05-08 17:15:13 -07:00
writeback.c bcache: correct cache_dirty_target in __update_writeback_rate() 2017-09-06 08:17:33 -06:00
writeback.h bcache: correct cache_dirty_target in __update_writeback_rate() 2017-09-06 08:17:33 -06:00