From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262015AbVAHKgy (ORCPT ); Sat, 8 Jan 2005 05:36:54 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261997AbVAHKdM (ORCPT ); Sat, 8 Jan 2005 05:33:12 -0500 Received: from gold.muskoka.com ([216.123.107.5]:45471 "EHLO gold.muskoka.com") by vger.kernel.org with ESMTP id S261856AbVAHKcS (ORCPT ); Sat, 8 Jan 2005 05:32:18 -0500 Message-ID: <41DF9AC1.2010609@muskoka.com> Date: Sat, 08 Jan 2005 03:33:05 -0500 From: Paul Gortmaker User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.3.1) Gecko/20030425 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Linux Kernel Mailing List CC: Jeff Garzik , Alan Cox Subject: Re: [PATCH] 2.6.9 Use skb_padto() in drivers/net/8390.c] References: <41DED9FA.7080106@pobox.com> In-Reply-To: <41DED9FA.7080106@pobox.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > From: Alan Cox > > >This was done because it benchmarked materially faster than the >skb_padto version you just reverted. Its only 64 bytes on the stack and >its cached. > >ie the old 8390 code was quite intentional and done because it commonly >occurs on very old machines where clock count matters. Because of its >commonness I actually hand optimised this one when I did the original >fixes to avoid doing extra memory allocations. > >Summary: Please revert. > >Alan > > Is it possible that skb_padto has since got its act together? Reason I ask is that I just dusted off a crusty 386dx40 (doesn't get much older than that) with a wd8013. As a basic test, I did ttcp Tx tests with small packets and they came out to all intents and purposes, identical. Kernel was 2.6.10, with stack vs skb_padto, each size test ran 3 times, even tested packets bigger than ETH_ZLEN as a (hopefully) invariant. I've attached the edited down results below. Paul. --- Stock 2.6.10 kernel with 8390 doing the padding --- ttcp-t: buflen=1, nbuf=32768, align=16384/0, port=5001 tcp -> g 1: ttcp-t: 32768 bytes in 32.81 real seconds = 0.98 KB/sec +++ ttcp-t: 32768 I/O calls, msec/call = 1.03, calls/sec = 998.79 ttcp-t: 3.5user 29.2sys 0:32real 99% 0i+0d 0maxrss 0+0pf 0+23csw 2: ttcp-t: 32768 bytes in 32.80 real seconds = 0.98 KB/sec +++ ttcp-t: 32768 I/O calls, msec/call = 1.03, calls/sec = 998.99 ttcp-t: 3.7user 29.0sys 0:32real 99% 0i+0d 0maxrss 0+0pf 0+23csw 3: ttcp-t: 32768 bytes in 32.80 real seconds = 0.98 KB/sec +++ ttcp-t: 32768 I/O calls, msec/call = 1.02, calls/sec = 999.10 ttcp-t: 0.2user 32.5sys 0:32real 99% 0i+0d 0maxrss 0+0pf 0+23csw ttcp-t: buflen=10, nbuf=32768, align=16384/0, port=5001 tcp -> g 1: ttcp-t: 327680 bytes in 32.80 real seconds = 9.76 KB/sec +++ ttcp-t: 32768 I/O calls, msec/call = 1.02, calls/sec = 999.06 ttcp-t: 1.3user 31.4sys 0:32real 99% 0i+0d 0maxrss 0+0pf 0+23csw 2: ttcp-t: 327680 bytes in 32.80 real seconds = 9.76 KB/sec +++ ttcp-t: 32768 I/O calls, msec/call = 1.03, calls/sec = 999.02 ttcp-t: 1.5user 31.2sys 0:32real 99% 0i+0d 0maxrss 0+0pf 0+23csw 3: ttcp-t: 327680 bytes in 32.80 real seconds = 9.76 KB/sec +++ ttcp-t: 32768 I/O calls, msec/call = 1.02, calls/sec = 999.07 ttcp-t: 2.3user 30.3sys 0:32real 99% 0i+0d 0maxrss 0+0pf 0+23csw ttcp-t: buflen=40, nbuf=32768, align=16384/0, port=5001 tcp -> g 1: ttcp-t: 1310720 bytes in 32.80 real seconds = 39.02 KB/sec +++ ttcp-t: 32768 I/O calls, msec/call = 1.03, calls/sec = 998.96 ttcp-t: 14.2user 18.5sys 0:32real 99% 0i+0d 0maxrss 0+0pf 0+23csw 2: ttcp-t: 1310720 bytes in 32.82 real seconds = 39.00 KB/sec +++ ttcp-t: 32768 I/O calls, msec/call = 1.03, calls/sec = 998.37 ttcp-t: 14.6user 18.1sys 0:32real 99% 0i+0d 0maxrss 0+0pf 0+24csw 3: ttcp-t: 1310720 bytes in 32.80 real seconds = 39.02 KB/sec +++ ttcp-t: 32768 I/O calls, msec/call = 1.03, calls/sec = 998.91 ttcp-t: 15.1user 17.5sys 0:32real 99% 0i+0d 0maxrss 0+0pf 0+23csw ttcp-t: buflen=100, nbuf=32768, align=16384/0, port=5001 tcp -> g 1: ttcp-t: 3276800 bytes in 32.86 real seconds = 97.37 KB/sec +++ ttcp-t: 32768 I/O calls, msec/call = 1.03, calls/sec = 997.05 ttcp-t: 0.1user 32.7sys 0:32real 99% 0i+0d 0maxrss 0+0pf 0+23csw 2: ttcp-t: 3276800 bytes in 32.93 real seconds = 97.19 KB/sec +++ ttcp-t: 32768 I/O calls, msec/call = 1.03, calls/sec = 995.22 ttcp-t: 0.1user 32.7sys 0:32real 99% 0i+0d 0maxrss 0+0pf 0+24csw 3: ttcp-t: 3276800 bytes in 32.83 real seconds = 97.47 KB/sec +++ ttcp-t: 32768 I/O calls, msec/call = 1.03, calls/sec = 998.12 ttcp-t: 0.0user 32.7sys 0:32real 99% 0i+0d 0maxrss 0+0pf 0+22csw --- 2.6.10 Kernel with 8390 calling kernel's skb_padto --- ttcp-t: buflen=1, nbuf=32768, align=16384/0, port=5001 tcp -> g 1: ttcp-t: 32768 bytes in 32.81 real seconds = 0.98 KB/sec +++ ttcp-t: 32768 I/O calls, msec/call = 1.03, calls/sec = 998.68 ttcp-t: 1.5user 31.2sys 0:32real 99% 0i+0d 0maxrss 0+0pf 0+23csw 2: ttcp-t: 32768 bytes in 32.79 real seconds = 0.98 KB/sec +++ ttcp-t: 32768 I/O calls, msec/call = 1.02, calls/sec = 999.36 ttcp-t: 4.3user 28.3sys 0:32real 99% 0i+0d 0maxrss 0+0pf 0+24csw 3: ttcp-t: 32768 bytes in 32.80 real seconds = 0.98 KB/sec +++ ttcp-t: 32768 I/O calls, msec/call = 1.03, calls/sec = 998.99 ttcp-t: 9.3user 23.3sys 0:32real 99% 0i+0d 0maxrss 0+0pf 0+24csw ttcp-t: buflen=10, nbuf=32768, align=16384/0, port=5001 tcp -> g 1: ttcp-t: 327680 bytes in 32.80 real seconds = 9.76 KB/sec +++ ttcp-t: 32768 I/O calls, msec/call = 1.02, calls/sec = 999.14 ttcp-t: 12.5user 20.2sys 0:32real 99% 0i+0d 0maxrss 0+0pf 0+23csw 2: ttcp-t: 327680 bytes in 32.78 real seconds = 9.76 KB/sec +++ ttcp-t: 32768 I/O calls, msec/call = 1.02, calls/sec = 999.52 ttcp-t: 1.2user 31.5sys 0:32real 99% 0i+0d 0maxrss 0+0pf 0+23csw 3: ttcp-t: 327680 bytes in 32.78 real seconds = 9.76 KB/sec +++ ttcp-t: 32768 I/O calls, msec/call = 1.02, calls/sec = 999.60 ttcp-t: 5.6user 27.1sys 0:32real 99% 0i+0d 0maxrss 0+0pf 0+24csw ttcp-t: buflen=40, nbuf=32768, align=16384/0, port=5001 tcp -> g 1: ttcp-t: 1310720 bytes in 32.80 real seconds = 39.03 KB/sec +++ ttcp-t: 32768 I/O calls, msec/call = 1.02, calls/sec = 999.09 ttcp-t: 17.3user 15.4sys 0:32real 99% 0i+0d 0maxrss 0+0pf 0+22csw 2: ttcp-t: 1310720 bytes in 32.80 real seconds = 39.02 KB/sec +++ ttcp-t: 32768 I/O calls, msec/call = 1.03, calls/sec = 999.00 ttcp-t: 18.2user 14.5sys 0:32real 99% 0i+0d 0maxrss 0+0pf 0+24csw 3: ttcp-t: 1310720 bytes in 32.80 real seconds = 39.03 KB/sec +++ ttcp-t: 32768 I/O calls, msec/call = 1.02, calls/sec = 999.06 ttcp-t: 17.8user 14.9sys 0:32real 99% 0i+0d 0maxrss 0+0pf 0+22csw ttcp-t: buflen=100, nbuf=32768, align=16384/0, port=5001 tcp -> g 1: ttcp-t: 3276800 bytes in 32.81 real seconds = 97.54 KB/sec +++ ttcp-t: 32768 I/O calls, msec/call = 1.03, calls/sec = 998.77 ttcp-t: 0.0user 32.7sys 0:32real 99% 0i+0d 0maxrss 0+0pf 0+23csw 2: ttcp-t: 3276800 bytes in 32.82 real seconds = 97.51 KB/sec +++ ttcp-t: 32768 I/O calls, msec/call = 1.03, calls/sec = 998.54 ttcp-t: 0.0user 32.7sys 0:32real 99% 0i+0d 0maxrss 0+0pf 0+23csw 3: ttcp-t: 3276800 bytes in 32.83 real seconds = 97.46 KB/sec +++ ttcp-t: 32768 I/O calls, msec/call = 1.03, calls/sec = 997.99 ttcp-t: 0.0user 32.7sys 0:32real 99% 0i+0d 0maxrss 0+0pf 0+23csw