Re: [PATCH] tcp: splice as many packets as possible at once

David Miller
2009-01-19T03:27:32Z

From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Mon, 19 Jan 2009 14:08:44 +1100

> On Mon, Jan 19, 2009 at 01:42:06AM +0100, Willy Tarreau wrote:
> >
> > Just for the record, I've now re-integrated those changes in a test kernel
> > that I booted on my 10gig machines. I have updated my user-space code in
> > haproxy to run a new series of tests. Eventhough there is a memcpy(), the
> > results are EXCELLENT (on a C2D 2.66 GHz using Myricom's Myri10GE NICs) :
> >
> > - 4.8 Gbps at 100% CPU using MTU=1500 without LRO
> > (3.2 Gbps at 100% CPU without splice)
>
> One thing to note is that Myricom's driver probably uses page
> frags which means that you're not actually triggering the copy.

Right.

And this is also the only reason why jumbo MTU worked :-)