From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [RFC][PATCH] iproute: Faster ip link add, set and delete
Date: Tue, 26 Mar 2013 08:31:00 -0700
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References: <CD773D0D.7614%blourdel@juniper.net>
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Cc: Stephen Hemminger <stephen@networkplumber.org>,
	"Eric W. Biederman" <ebiederm@xmission.com>,
	"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
	Serge Hallyn <serge.hallyn@ubuntu.com>
To: Benoit Lourdelet <blourdel@juniper.net>
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On Tue, 2013-03-26 at 11:51 +0000, Benoit Lourdelet wrote:

> The script to delete:
> for d in /sys/class/net/veth*; do
> 	ip link del `basename $d` 2>/dev/null || true
> Done
> 
> There is a very good improvement in deletion.

I can do better ;)

If you are really doing this kind of things, you could use :

rmmod veth

Note that "ip" command supports a batch mode

ip -batch filename

In this case, the caching is done only once.

Eric, Stephen, one possibility would be to use the cache only in batch
mode.

Anyway caching is wrong because several users can use ip command at the
same time.