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From: "Michal Kubeček" <mkubecek@suse.cz>
To: netfilter@vger.kernel.org
Cc: Jan Engelhardt <jengelh@medozas.de>
Subject: Re: limit module timer precision issue
Date: Thu, 13 Oct 2011 13:23:04 +0200	[thread overview]
Message-ID: <201110131323.04339.mkubecek@suse.cz> (raw)
In-Reply-To: <alpine.LNX.2.01.1110131214530.28308@frira.zrqbmnf.qr>

On Thursday 13 of October 2011, Jan Engelhardt wrote:
> >Not exactly. With "--limit-burst 1", no more than one packet per
> >jiffy can pass the test. You may have only 30 NEW packets per
> >second but it doesn't mean one packet every 1/30 s. And if there
> >are two (or more) NEW packets within one jiffy, only the first
> >passes the first rule.
> 
> One packet per time quantum (which is 1 second here, not 1 jiffy).

I don't think so. With "--limit 2000/s --limit-burst 1" I can pass much 
more than one packet per second (but no more than 1000 per second with 
HZ=1000).

In fact, kernel doesn't even get this information, it works only with 
rate and it gets exactly the same value from iptables command with e.g. 
'3600/h', '60/m' and '1/s'.

                                                         Michal Kubeček

  reply	other threads:[~2011-10-13 11:23 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-10-13  1:43 limit module timer precision issue abirvalg
2011-10-12 22:57 ` Jan Engelhardt
2011-10-13  7:10 ` Michal Kubeček
2011-10-13 10:15   ` Jan Engelhardt
2011-10-13 11:23     ` Michal Kubeček [this message]
2011-10-13 12:32       ` Jan Engelhardt
2011-10-13 13:08         ` Michal Kubeček
2011-10-13 19:59 ` fuzzy_4711

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