From: Ming Lei <ming.lei@redhat.com>
To: linux-kernel@vger.kernel.org, linux-block@vger.kernel.org
Cc: Ming Lei <ming.lei@redhat.com>, Sagi Grimberg <sagi@grimberg.me>,
Tejun Heo <tj@kernel.org>, Christoph Hellwig <hch@lst.de>,
Jens Axboe <axboe@kernel.dk>,
Bart Van Assche <bvanassche@acm.org>
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 [thread overview]
Message-ID: <20200825101248.8027-1-ming.lei@redhat.com> (raw)
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
next reply other threads:[~2020-08-25 10:13 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-08-25 10:12 Ming Lei [this message]
2020-08-25 10:12 ` [PATCH 1/2] percpu_ref: reduce memory footprint of percpu_ref in fast path Ming Lei
2020-08-31 9:48 ` [percpu_ref] 13f0f97539: blktests.block.027.fail kernel test robot
2020-08-25 10:12 ` [PATCH 2/2] block: move 'q_usage_counter' into front of 'request_queue' Ming Lei
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