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From: Valdis.Kletnieks@vt.edu (Valdis.Kletnieks at vt.edu)
To: kernelnewbies@lists.kernelnewbies.org
Subject: epoll improvements
Date: Thu, 16 Oct 2014 13:02:13 -0400	[thread overview]
Message-ID: <47342.1413478933@turing-police.cc.vt.edu> (raw)
In-Reply-To: Your message of "Thu, 16 Oct 2014 14:09:05 +0200." <trinity-842dea81-708d-4ef5-86ad-68daf6f7d7e5-1413461344834@3capp-mailcom-bs07>

On Thu, 16 Oct 2014 14:09:05 +0200, "Nev Ikte" said:

> I've tried to reproduce it with a single client
> and basically, if ep_poll() is able to find an event or the timeout is 0,
> the latency is down to 5usec, otherwise if it enters the waitqueue
> the latency goes up to 10-25usec, which impact the application performance.

Is it possible that what you're actually measuring here is your CPU's
latency coming out of a sleep state if every task is in a wait queue?
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  parent reply	other threads:[~2014-10-16 17:02 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-10-16 12:09 epoll improvements Nev Ikte
2014-10-16 12:17 ` Greg KH
2014-10-16 12:48   ` Jason Ball
2014-10-16 17:02 ` Valdis.Kletnieks at vt.edu [this message]
2014-10-17 16:47   ` michi1 at michaelblizek.twilightparadox.com

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