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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Fri, 22 Jun 2018 19:05:14 +0900
Message-ID: <CA+55aFxfdnFUkDQX6LCFXz=Q9_KbSy3bjqb6zCj9VKj6fA42VA@mail.gmail.com>
Subject: Re: [lkp-robot] [fs] 3deb642f0d: will-it-scale.per_process_ops -8.8% regression
To:     Christoph Hellwig <hch@lst.de>
Cc:     kernel test robot <xiaolong.ye@intel.com>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "Darrick J. Wong" <darrick.wong@oracle.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        LKP <lkp@01.org>
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On Fri, Jun 22, 2018 at 7:02 PM Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
> Get your act together. Don't uglify and slow down everything else just
> because you're concentrating only on aio.

.. and seriously, poll and select are timing-critical. There are many
real loads where they show up as *the* thing in kernel profiles.

aio is a distant distant second cousin. You need to make sure poll and
select are prioritized, and aio should be a "if we can do this
cleanly" case.

                Linus