From: Denys Fedoryshchenko <denys@visp.net.lb>
Organization: Virtual ISP
To: Eric Dumazet <dada1@cosmosbay.com>
Subject: Re: loaded router, excessive getnstimeofday in oprofile
Date: Thu, 28 Aug 2008 22:55:29 +0300
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Cc: Andi Kleen <andi@firstfloor.org>, Joe Malicki <jmalicki@metacarta.com>,
       David Miller <davem@davemloft.net>, johnpol@2ka.mipt.ru,
       netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
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On Thursday 28 August 2008, Eric Dumazet wrote:
> OK, please try oprofile with call graph analysis.
I did already. Even because most of programs (except ripd/zebra) can be 
killed, and i kill them, it doesn't change almost anything.

it seems heavy things causing instability:

1)HTB (resolution can be lowered to improve performance, i will try Jarek 
patch soon)
2)ocassionally ping/tcpdump other SO_TIMESTAMP users
3)Probably softlockup detection. Disabled already, i will come back to it 
soon, if it is required.

One of other issues i notice - "CACHE MISS" cause maybe almost 5-10% in 
oprofile in u32, but i am not sure it is interesting subject to discuss. I 
have to optimize all my iproute2 rules first.

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