From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 30 Jan 2001 20:06:05 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 30 Jan 2001 20:05:55 -0500 Received: from shell.cyberus.ca ([209.195.95.7]:44983 "EHLO shell.cyberus.ca") by vger.kernel.org with ESMTP id ; Tue, 30 Jan 2001 20:05:44 -0500 Date: Tue, 30 Jan 2001 20:04:51 -0500 (EST) From: jamal To: Ingo Molnar cc: Ion Badulescu , Andrew Morton , lkml , "netdev@oss.sgi.com" Subject: Re: Still not sexy! (Re: sendfile+zerocopy: fairly sexy (nothing to do with ECN) In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 31 Jan 2001, Ingo Molnar wrote: > > On Tue, 30 Jan 2001, jamal wrote: > > > Kernel | tput | sender-CPU | receiver-CPU | > > ------------------------------------------------- > > 2.4.0-pre3 | 99MB/s | 87% | 23% | > > NSF | | | | > > ------------------------------------------------- > > 2.4.0-pre3 | 68 | 8% | 8% | > > +ZC SF | MB/s | | | > > ------------------------------------------------- > > isnt the CPU utilization difference amazing? :-) > With a caveat, sadly ;-> ttcp uses times() system call (or a diff of times() one at the beggining and another at the end). So the cpu measurements are not reflective. > a couple of questions: > > - is this UDP or TCP based? (UDP i guess) > TCP > - what wsize/rsize are you using? How do these requests look like on the > network, ie. are they suffieciently MTU-sized? yes. writes vary from 8K->64K but not much difference over the long period of time. > > - what happens if you run multiple instances of the testcode, does it > saturate bandwidth (or CPU)? This is something of great interest. I havent tried it. I should. I suspect this would be where the value of the ZC changes will become evident. cheers, jamal - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/