From: Hagen Paul Pfeifer <hagen@jauu.net>
To: Octavian Purdila <opurdila@ixiacom.com>
Cc: netdev@vger.kernel.org
Subject: Re: [PATCH next-next-2.6] netdev: better dev_name_hash
Date: Sun, 25 Oct 2009 21:17:14 +0100 [thread overview]
Message-ID: <20091025201714.GA20987@nuttenaction> (raw)
In-Reply-To: <200910252158.53921.opurdila@ixiacom.com>
* Octavian Purdila | 2009-10-25 21:58:53 [+0200]:
>
>The current dev_name_hash is not very good at spreading entries when a
>large number of interfaces of the same type (e.g. ethXXXXX) are used.
>
>Here are some performance numbers for creating 16000 dummy interfaces with
>and without the patch (with per device sysctl entries disabled)
>
> With patch Without patch
>
> real 0m 2.27s real 0m 4.32s
> user 0m 0.00s user 0m 0.00s
> sys 0m 1.13s sys 0m 2.16s
Can you rerun the test with jhash() as the hash function? Just for clearness -
the spreading of jhash should be more uniformly distributed. At the end: where
is the threshold where a more accurate hash function is superior.
HGN
--
Hagen Paul Pfeifer <hagen@jauu.net> || http://jauu.net/
Telephone: +49 174 5455209 || Key Id: 0x98350C22
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next prev parent reply other threads:[~2009-10-25 20:23 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-10-25 19:58 [PATCH next-next-2.6] netdev: better dev_name_hash Octavian Purdila
2009-10-25 20:17 ` Hagen Paul Pfeifer [this message]
2009-10-25 21:24 ` Eric Dumazet
2009-10-25 21:55 ` Octavian Purdila
2009-10-25 22:41 ` Hagen Paul Pfeifer
2009-10-25 22:45 ` Octavian Purdila
2009-10-26 5:28 ` Eric Dumazet
2009-10-26 13:07 ` Krishna Kumar2
2009-10-26 14:31 ` Octavian Purdila
2009-10-26 14:55 ` Eric Dumazet
2009-10-26 15:52 ` Octavian Purdila
2009-10-26 16:55 ` Stephen Hemminger
2009-10-26 17:45 ` Stephen Hemminger
2009-10-27 1:24 ` David Miller
2009-10-27 1:40 ` Eric Dumazet
2009-10-26 6:30 ` Stephen Hemminger
2009-10-26 7:48 ` Eric Dumazet
2009-10-26 4:43 ` Stephen Hemminger
2009-10-26 22:36 ` [PATCH] dcache: better name hash function Stephen Hemminger <shemminger@vyatta.com>, Al Viro
2009-10-27 2:45 ` Eric Dumazet
2009-10-27 3:53 ` Stephen Hemminger
2009-10-27 16:38 ` Rick Jones
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