From: "David S. Miller" <davem@davemloft.net>
To: johnpol@2ka.mipt.ru
Cc: netdev@vger.kernel.org, caitlinb@broadcom.com, kelly@au1.ibm.com,
rusty@rustcorp.com.au
Subject: Re: Initial benchmarks of some VJ ideas [mmap memcpy vs copy_to_user].
Date: Mon, 08 May 2006 13:15:47 -0700 (PDT) [thread overview]
Message-ID: <20060508.131547.73910171.davem@davemloft.net> (raw)
In-Reply-To: <20060508195132.GB19091@2ka.mipt.ru>
From: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Date: Mon, 8 May 2006 23:51:32 +0400
> Since nocopy is actually equal to dma into mapped buffer,
> so we get something close to 6 times less CPU usage, and if it can be
> lineary transferred into performance gain, we found where the most
> significant part of VJ channels lives.
Van's machines were cpu limited. And once cpu limit was removed,
they became bus bandwidth limited.
> Unfortunately it is not backward compatible with recv() system call,
> and requires major changes in application to use this advantage.
I have stopped believing that compatible API for getting top
performance in networking receive is possible a very long time ago.
ABI change is an absolutely requirement.
next prev parent reply other threads:[~2006-05-08 20:17 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-05-08 12:24 Initial benchmarks of some VJ ideas [mmap memcpy vs copy_to_user] Evgeniy Polyakov
2006-05-08 19:51 ` Evgeniy Polyakov
2006-05-08 20:15 ` David S. Miller [this message]
2006-05-10 19:58 ` David S. Miller
2006-05-11 6:40 ` Evgeniy Polyakov
2006-05-11 7:07 ` David S. Miller
2006-05-11 8:30 ` Evgeniy Polyakov
2006-05-11 16:18 ` Evgeniy Polyakov
2006-05-11 18:54 ` David S. Miller
2006-05-11 19:30 ` Rick Jones
2006-05-12 7:54 ` Evgeniy Polyakov
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