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Date: Wed, 11 Feb 2004 03:01:25 -0600 (CST)
From: Mike Silbersack <silby@silby.com>
To: Chuck Swiger <cswiger@mac.com>
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cc: Bjorn Eikeland <bjorn@eikeland.info>
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Subject: Re: dummynet = local taffic > 100ms - help!
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On Tue, 10 Feb 2004, Chuck Swiger wrote:

> I seem to recall some issues with setting HZ very fast, in that it breaks the
> uniqueness assumptions made by TCP sequence generation if HZ > 1000.  Dummynet
> does want better than the standard 10ms granularity (HZ=100), so perhaps you
> might try HZ=1000 and see whether that makes any difference.
>
> You might also consider increasing the queue length of your pipes when using
> prioriziation--- are you seeing packets being dropped?
>
> --
> -Chuck

It breaks TCP Timestamp generation slightly, but that's not likely to
break much of anything in practice.  TCP sequence numbers should be ok,
but there may be overflow if you go to something > 10000... I should check
one of these days.

Mike "Silby" Silbersack