From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jamal Hadi Salim <jhs@mojatatu.com>
Subject: Re: What's the right way to use a *large* number of source addresses?
Date: Sat, 24 May 2014 08:06:41 -0400
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To: Eric Dumazet <eric.dumazet@gmail.com>,
	sowmini varadhan <sowmini05@gmail.com>
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On 05/23/14 10:14, Eric Dumazet wrote:

> Use the batch mode, and it will be much faster than ifconfig, as
> ifconfig does not support this mode (you need one fork()/exec() per IP
> address)
>
> ip -batch filename
>

The address dumping algorithm is a very likely contributor as well.
It tries to remember indices and then skips on the next iteration
all the way to where it left off.... has never been a big deal until
someone tries a substantial number of addresses.

cheers,
jamal