Messages in this thread | ![/](/images/icornerl.gif) | | From | Ming Lei <> | Subject | [PATCH 0/2] percpu_ref & block: reduce memory footprint of percpu_ref in fast path | Date | Tue, 25 Aug 2020 18:12:46 +0800 |
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Hi,
The 1st patch removes memory footprint of percpu_ref in fast path from 7 words to 2 words, since it is often used in fast path and embedded in user struct.
The 2nd patch moves .q_usage_counter to 1st cacheline of 'request_queue'.
Simple test on null_blk shows ~2% IOPS boost on one 16cores(two threads per core) machine, dual socket/numa.
Ming Lei (2): percpu_ref: reduce memory footprint of percpu_ref in fast path block: move 'q_usage_counter' into front of 'request_queue'
drivers/infiniband/sw/rdmavt/mr.c | 2 +- include/linux/blkdev.h | 3 +- include/linux/percpu-refcount.h | 43 +++++++++---- lib/percpu-refcount.c | 101 ++++++++++++++++++++---------- 4 files changed, 101 insertions(+), 48 deletions(-)
Cc: Sagi Grimberg <sagi@grimberg.me> Cc: Tejun Heo <tj@kernel.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Bart Van Assche <bvanassche@acm.org> -- 2.25.2
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