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From: Adrian Chadd <adrian@freebsd.org>
To: Max Laier <max@love2party.net>
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Cc: Nick Rogers <ncrogers@gmail.com>, freebsd-hackers@freebsd.org
Subject: Re: arp(8) performance w/ many aliases assigned to an interface
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On 10 June 2010 05:21, Max Laier <max@love2party.net> wrote:

>> Is there something that can be done to speedup the call to
>> if_indextoname(), or would it be worthwhile for me to submit a patch that
>> adds the ability to skip the interface lookup as an arp(8) option?
>
> how about the attached:
>

This patch only short-circuits the lookup for a specific case - lots
of entries with the same ifname. What about other situations - say,
alternating interfaces in ARP?

I read if_indextoname(). The problem is that each call is sucking down
the ifaddrs table and looking for the index. Is this likely to be a
problem in other situations, rather than just /usr/sbin/arp ?


Adrian