From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bin Ren Subject: Re: [PATCH] Network Checksum Removal Date: Mon, 23 May 2005 22:52:42 +0100 Message-ID: <8ae7802505052314526e303a24@mail.gmail.com> References: <20050520233015.GA26305@us.ibm.com> <8ae78025050523085662a94019@mail.gmail.com> <8ae7802505052309067d88f174@mail.gmail.com> <200505231116.16964.jdmason@us.ibm.com> <8ae7802505052309362c2fb00e@mail.gmail.com> <32fa5a4ad70f86ee5637d30ffc890017@cl.cam.ac.uk> <8ae780250505231255a0cea3b@mail.gmail.com> <3781733093cae2d97c7358f29073f250@cl.cam.ac.uk> Reply-To: bin.ren@cl.cam.ac.uk Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <3781733093cae2d97c7358f29073f250@cl.cam.ac.uk> Content-Disposition: inline List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Keir Fraser Cc: Andrew Theurer , xen-devel@lists.xensource.com, Jon Mason List-Id: xen-devel@lists.xenproject.org On 5/23/05, Keir Fraser wrote: > What happens to CPU usage in dom1 when tx checksumming is disabled? dom1->dom0: 70.7% id, 0.0% wa, 1.7% hi, 15.0% si dom1->external: 20.0% id, 0.0% wa, 0.7% hi, 60.0% si dom1->dom2: 77.7% id, 0.0% wa, 1.0% hi, 9.3% si >=20 > Overall though these are the kind of results I would expect. Linux > usually does csumming at the same time as it has to do a copy anyway, > and it ends up being limited by memory/L2-cache bandwidth, not the > extra computation. But the offload extensions haven't cost much to > implement and there are probably cases where it helps a little. >=20 > Maybe I'm being pessimistic though: Can you reproduce the rather more > impressive speedups that you previously saw, Jon? >=20 > -- Keir >=20 >=20 > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xensource.com > http://lists.xensource.com/xen-devel >