Hi,
The 1st 2 patch improves ctx->lock uses, and it is observed that IOPS
may be improved by ~5% in rand IO test on MegaRaid SAS run by Kashyap.
The 3rd patch fixes rand IO performance regression on MegaRaid SAS
test, still reported by Kashyap.
V3:
- export dispatch busy from debugfs as suggested by Jens
- add comment on blk_mq_update_hctx_busy() as suggested by Christoph
V2:
- fix list corruption in patch 1/3
Ming Lei (3):
blk-mq: use list_splice_tail_init() to insert requests
blk-mq: only attempt to merge bio if there is rq in sw queue
blk-mq: dequeue request one by one from sw queue iff hctx is busy
block/blk-mq-debugfs.c | 9 +++++++++
block/blk-mq-sched.c | 14 ++++----------
block/blk-mq.c | 44 ++++++++++++++++++++++++++++++++++++--------
include/linux/blk-mq.h | 3 ++-
4 files changed, 51 insertions(+), 19 deletions(-)
Cc: Kashyap Desai <[email protected]>
Cc: Laurence Oberman <[email protected]>
Cc: Omar Sandoval <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Bart Van Assche <[email protected]>
Cc: Hannes Reinecke <[email protected]>
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2.9.5
