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From: Alexey Vlasov <renton@renton.name>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	netdev <netdev@vger.kernel.org>
Subject: Re: Packet time delays on multi-core systems
Date: Thu, 30 Sep 2010 16:30:48 +0400	[thread overview]
Message-ID: <20100930123048.GA4094@beaver.vrungel.ru> (raw)
In-Reply-To: <1285796721.5211.156.camel@edumazet-laptop>

On Wed, Sep 29, 2010 at 11:45:21PM +0200, Eric Dumazet wrote:
> But if you send SYN packets in the same time, (logged), this might
> slow
> down the reception (and answers) of ICMP frames. LOG target can be
> quite
> expensive...

Yes, it's clear that  some slow down can appear, but 100 ms is too much,
and this happens at 200 SYN packets in 2 minutes just as in my example.
On old servers where some tx/rx are missing in NIC card I don't see
such a situation even at more then 1000 SYN-packets per sec.

> Is using other rules gives same problem ?
>
> iptables -A OUTPUT -p tcp -m tcp --dport 80 --tcp-flags

No, only LOG gives such a scheme.

-- 
BRGDS. Alexey Vlasov.

  parent reply	other threads:[~2010-09-30 12:32 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20100929191851.GC86786@beaver.vrungel.ru>
2010-09-29 21:45 ` Packet time delays on multi-core systems Eric Dumazet
2010-09-30  6:24   ` Alexey Vlasov
2010-09-30  6:33     ` Eric Dumazet
2010-09-30 12:23       ` Alexey Vlasov
2010-09-30 12:44         ` Eric Dumazet
2010-09-30 17:37           ` Alexey Vlasov
2010-09-30 18:03             ` Eric Dumazet
2010-09-30 18:15               ` Alexey Vlasov
2010-09-30 18:52                 ` Eric Dumazet
2010-10-01 10:16                   ` Alexey Vlasov
2010-10-01 12:59                     ` Eric Dumazet
2010-10-01 14:18                       ` Alexey Vlasov
2010-10-01 15:27                         ` Eric Dumazet
2010-10-01 18:54                           ` Jeff Kirsher
2010-09-30 12:30   ` Alexey Vlasov [this message]
2010-09-30 12:46     ` Eric Dumazet

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