From: Randy Dunlap <rdunlap@infradead.org>
To: "Brian C. Anderson" <brianderson@google.com>,
linux-fsdevel@vger.kernel.org
Cc: Victor Miura <vmiura@google.com>
Subject: Re: EPOLLET behavior and performance
Date: Fri, 14 Jul 2017 16:17:37 -0700 [thread overview]
Message-ID: <66862a8e-bdf3-af5c-335f-a65d2d4c6975@infradead.org> (raw)
In-Reply-To: <CAJiD4900vbGB9S26DKSh1bNXyf4_6rDBbgsv5W0cZhrHpibjZw@mail.gmail.com>
On 07/14/2017 03:45 PM, Brian C. Anderson wrote:
> Hi,
>
> Hoping I have the right email list for this topic.
fsdevel makes sense, but linux-kernel would probably provide more eyes
on it.
[snip]
> A few questions:
> 1) Do you see any problems with the approach I'm taking?
> 2) How concerning is backwards compatibility; especially regarding
> user code that may not handle being notified of EPOLLIN when the file
> isn't actually readable anymore.
> 3) A ~30% improvement is larger than I would have expected. Any clues
> what might be going on? I find it hard to believe improved cache
> locality explains it all.
> 4) Are there existing performance tests I can run the patch against?
You could try some of Davide Libenzi's epoll test programs, although they
need some updating before they are usable. See:
http://xmailserver.org/epoll_test.c {internals test}
http://xmailserver.org/totalmess.c {multithread test}
and http://marc.info/?l=linux-ia64&m=108458304114939&w=2 {performance}
--
~Randy
prev parent reply other threads:[~2017-07-14 23:17 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-07-14 22:45 EPOLLET behavior and performance Brian C. Anderson
2017-07-14 23:17 ` Randy Dunlap [this message]
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