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From: David Miller <davem@davemloft.net>
To: eric.dumazet@gmail.com
Cc: netdev@vger.kernel.org, hans.schillstrom@ericsson.com
Subject: Re: [PATCH net-next] ipv4: tcp: dont cache unconfirmed intput dst
Date: Wed, 27 Jun 2012 17:08:30 -0700 (PDT)	[thread overview]
Message-ID: <20120627.170830.811332455348620174.davem@davemloft.net> (raw)
In-Reply-To: <20120627.170101.99084491660488389.davem@davemloft.net>

From: David Miller <davem@davemloft.net>
Date: Wed, 27 Jun 2012 17:01:01 -0700 (PDT)

> There are quite a number of unwanted side effects from this change, so
> I think we'll have to revert unless you can fix up all of the relevant
> cases quickly.

Actually I've decided to revert it now.

Whilst this was a swell idea, there is no way for you to know if
we should really create a cached route or not.

Even if you could, there is a lot of logic you'll need to code up
so that, f.e., once we determine that we've got a DST_NOCACHE route
when we move to established state, we can insert it into the routing
cache and not mark it DST_NOCACHE any longer.

But even if we did that, we're going to eat 2 uncached route lookups
for every new incoming legitimate connection.

  reply	other threads:[~2012-06-28  0:08 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-06-27  9:14 [PATCH net-next] ipv4: tcp: dont cache unconfirmed intput dst Eric Dumazet
2012-06-27 22:34 ` David Miller
2012-06-27 23:44   ` David Miller
2012-06-28  0:01     ` David Miller
2012-06-28  0:08       ` David Miller [this message]
2012-06-28  5:08         ` Eric Dumazet
2012-06-28  5:13           ` Eric Dumazet
2012-06-28  5:22             ` David Miller

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