From mboxrd@z Thu Jan  1 00:00:00 1970
From: Hans de Goede <j.w.r.degoede@hhs.nl>
Subject: Re: cat /proc/net/tcp takes 0.5 seconds on x86_64
Date: Wed, 27 Aug 2008 11:07:54 +0200
Message-ID: <48B5196A.2080502@hhs.nl>
References: <E1KYCV5-0002jW-00@gondolin.me.apana.org.au>
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Cc: dada1@cosmosbay.com, davej@redhat.com, netdev@vger.kernel.org
To: Herbert Xu <herbert@gondor.apana.org.au>
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Herbert Xu wrote:
> Hans de Goede <j.w.r.degoede@hhs.nl> wrote:
>> Eric Dumazet wrote:
>>
>>> # dmesg | grep "TCP established hash"
>>> TCP established hash table entries: 262144 (order: 10, 4194304 bytes)
>>> # time cat /proc/net/tcp >/dev/null
>>>
>>> real    0m0.091s
>>> user    0m0.001s
>>> sys     0m0.090s
>> As quoted above my idle x86_64, using the exact same hash table size, running 
>> 2.6.27-rc2.git1 uses 0.520 seconds for that same command, thats a difference of 
>> more then a factor 50 !!
> 
> That looks like a factor of 5 to me, not 50.
> 

Erm, you are completely right ofcourse.

Regards,

Hans