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Subject: Re: [RFC PATCH 0/2] Optimise io_uring completion waiting
To:     "Pavel Begunkov (Silence)" <asml.silence@gmail.com>,
        Ingo Molnar <mingo@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        linux-block@vger.kernel.org, linux-kernel@vger.kernel.org
References: <cover.1568413210.git.asml.silence@gmail.com>
From:   Jens Axboe <axboe@kernel.dk>
Message-ID: <af5ba045-2ea8-b213-3625-354c10334540@kernel.dk>
Date:   Fri, 13 Sep 2019 18:31:11 -0600
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On 9/13/19 4:28 PM, Pavel Begunkov (Silence) wrote:
> From: Pavel Begunkov <asml.silence@gmail.com>
> 
> There could be a lot of overhead within generic wait_event_*() used for
> waiting for large number of completions. The patchset removes much of
> it by using custom wait event (wait_threshold).
> 
> Synthetic test showed ~40% performance boost. (see patch 2)

Nifty, from an io_uring perspective, I like this a lot.

The core changes needed to support it look fine as well. I'll await
Peter/Ingo's comments on it.

-- 
Jens Axboe