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Date:   Tue, 6 Oct 2020 15:41:00 +0800
From:   Ming Lei <ming.lei@redhat.com>
To:     linux-kernel@vger.kernel.org, linux-block@vger.kernel.org
Cc:     Veronika Kabatova <vkabatov@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: Re: [PATCH V7 0/2] percpu_ref & block: reduce memory footprint of
 percpu_ref in fast path
Message-ID: <20201006074100.GA26059@T590>
References: <20201001154842.26896-1-ming.lei@redhat.com>
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On Thu, Oct 01, 2020 at 11:48:40PM +0800, Ming Lei wrote:
> 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.
> 
> V7:
> 	- add comments about reason for struct split

Hello Jens

Can you consider to merge the patchset in block tree if you are fine?


Thanks,
Ming