Subject: Re: [PATCH next-next-2.6] netdev: better dev_name_hash

From: Stephen Hemminger <[email-masked]>
Date: Sun, 25 Oct 2009 21:43:57 -0700

On Sun, 25 Oct 2009 21:58:53 +0200
Octavian Purdila <[email-masked]> wrote:

> 
> 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
> 
> Signed-off-by: Octavian Purdila <[email-masked]>
> ---
>  net/core/dev.c |    8 +++++++-
>  1 files changed, 7 insertions(+), 1 deletions(-)

My $.02 would for fixing full name hash because other usages would
benefit as well.  Inventing special case for network devices seems
unnecessary.

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