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Date: Tue, 6 Mar 2007 21:15:00 +0300
From: "Vladimir B. Savkin" <master@sectorb.msk.ru>
To: Eric Dumazet <dada1@cosmosbay.com>
Cc: netdev@vger.kernel.org, Andi Kleen <ak@suse.de>,
       Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
       David Miller <davem@davemloft.net>, hawk@diku.dk,
       harry@atmos.washington.edu, linux-kernel@vger.kernel.org,
       Rick Jones <rick.jones2@hp.com>
Subject: Re: Packet timestamps (was: Re: Network performance degradation from 2.6.11.12 to 2.6.16.20)
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On Tue, Mar 06, 2007 at 04:16:24PM +0100, Eric Dumazet wrote:
> 
> It would be better to name the tunable "disable_timestamps", default 0 of 
> course.... 

I agree.
If networking maintainers are interested, I surely can prepare a patch.

But IMO some way to force TSC usage on x86_64 will be even better.

> It would better describe what your patch is actually doing : Even if a tcpdump 
> is running (so asking for timestamps), it wont have them because the sysctl 
> disabled them.

Well, tcpdump will have timestamps, but taken at wrong moment.
But some other applications (that use ip_queue, ulog etc.) will not,
as I understand.

> 
> Thank you
> 
~
:wq
                                        With best regards, 
                                           Vladimir Savkin.