Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030204AbWCWPQv (ORCPT ); Thu, 23 Mar 2006 10:16:51 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932434AbWCWPQv (ORCPT ); Thu, 23 Mar 2006 10:16:51 -0500 Received: from mtagate2.uk.ibm.com ([195.212.29.135]:57761 "EHLO mtagate2.uk.ibm.com") by vger.kernel.org with ESMTP id S932375AbWCWPQu (ORCPT ); Thu, 23 Mar 2006 10:16:50 -0500 Message-ID: <4422BBD9.40901@watson.ibm.com> Date: Thu, 23 Mar 2006 10:16:41 -0500 From: Shailabh Nagar User-Agent: Debian Thunderbird 1.0.2 (X11/20051002) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Greg KH CC: linux-kernel , Nick Piggin Subject: Re: [Patch 0/9] Performance References: <1142296834.5858.3.camel@elinux04.optonline.net> <20060314192824.GB27012@kroah.com> In-Reply-To: <20060314192824.GB27012@kroah.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5300 Lines: 136 Greg KH wrote: > On Mon, Mar 13, 2006 at 07:40:34PM -0500, Shailabh Nagar wrote: > >>This is the next iteration of the delay accounting patches >>last posted at >> http://www.ussg.iu.edu/hypermail/linux/kernel/0602.3/0893.html > > > Do you have any benchmark numbers with this patch applied and with it > not applied? Last I heard it was a measurable decrease for some > "important" benchmark results... > > thanks, > > greg k-h Here are some numbers for the latest set of posted patches using microbenchmarks hackbench, kernbench and lmbench. I was trying to get the real/big benchmark numbers too but it looks like getting a run whose numbers can be trusted will take a bit longer than expected. Preliminary runs of transaction processing benchmarks indicate that overhead actually decreases with the patch (as also seen in some of the lmbench numbers below). --Shailabh Results highlights - Configuring delay accounting adds < 0.5% overhead in most cases and even reduces overhead in some cases - Enabling delay accounting has similar results with a maximum overhead of 1.2% for hackbench , most other overheads < 1% and reduction in overhead in some cases Base Vanilla 2.6.16-rc6 kernel without any patches applied +patch Delay accounting configured but not enabled at boot +patch+enable Delay accounting enabled at boot but no stats read Hackbench --------- 200 groups, using sockets Elapsed time, in seconds, lower better %Ovhd Time Base 0 12.468 +patch 0.4% 12.523 +patch+enable 1.2% 12.622 Kernbench --------- Average of 5 iterations Elapsed time, in seconds, lower better %Ovhd Elapsed Base 0 195.776 +patch 0.2% 196.246 +patch+enable 0.3% 196.282 Lmbench ------- Processor, Processes - times in microseconds - smaller is better ---------------------------------------------------------------- Host OS Mhz null null open selct sig sig fork exec sh call I/O stat clos TCP inst hndl proc proc proc --------- ------------- ---- ---- ---- ---- ---- ----- ---- ---- ---- ---- ---- base Linux 2.6.16- 2783 0.17 0.33 5.17 6.49 13.4 0.64 2.61 146. 610. 9376 +patch Linux 2.6.16- 2781 0.17 0.32 4.75 5.85 13.0 0.64 2.62 145. 628. 9393 +patch+en Linux 2.6.16- 2784 0.17 0.32 4.71 6.14 13.4 0.64 2.60 150. 616. 9402 Context switching - times in microseconds - smaller is better ------------------------------------------------------------- Host OS 2p/0K 2p/16K 2p/64K 8p/16K 8p/64K 16p/16K 16p/64K ctxsw ctxsw ctxsw ctxsw ctxsw ctxsw ctxsw --------- ------------- ----- ------ ------ ------ ------ ------- ------- base Linux 2.6.16- 4.340 4.9600 7.3300 6.5700 30.3 10.4 36.0 +patch Linux 2.6.16- 4.390 4.9800 7.3100 6.5900 29.7 9.62000 35.8 +patch+en Linux 2.6.16- 4.560 5.0800 7.2400 5.6900 22.7 10.3 33.8 *Local* Communication latencies in microseconds - smaller is better ------------------------------------------------------------------- Host OS 2p/0K Pipe AF UDP RPC/ TCP RPC/ TCP ctxsw UNIX UDP TCP conn --------- ------------- ----- ----- ---- ----- ----- ----- ----- ---- base Linux 2.6.16- 4.340 15.9 12.2 18.3 24.9 21.5 29.1 45.3 +patch Linux 2.6.16- 4.390 15.7 11.8 18.6 22.2 22.0 29.1 44.8 +patch+en Linux 2.6.16- 4.560 15.6 12.1 18.9 25.3 21.9 27.1 45.1 File & VM system latencies in microseconds - smaller is better -------------------------------------------------------------- Host OS 0K File 10K File Mmap Prot Page Create Delete Create Delete Latency Fault Fault --------- ------------- ------ ------ ------ ------ ------- ----- ----- base Linux 2.6.16- 39.8 58.0 112.0 82.6 8417.0 0.838 2.00000 +patch Linux 2.6.16- 39.6 58.2 111.0 82.3 8392.0 0.864 2.00000 +patch+en Linux 2.6.16- 39.6 59.1 112.8 83.2 8308.0 0.821 2.00000 *Local* Communication bandwidths in MB/s - bigger is better ----------------------------------------------------------- Host OS Pipe AF TCP File Mmap Bcopy Bcopy Mem Mem UNIX reread reread (libc) (hand) read write --------- ------------- ---- ---- ---- ------ ------ ------ ------ ---- ----- base Linux 2.6.16- 676. 616. 620. 1658.0 2030.6 759.6 825.9 2032 1177. +patch Linux 2.6.16- 627. 165. 616. 1649.9 2030.9 766.1 834.1 2030 1187. +patch+en Linux 2.6.16- 633. 148. 603. 1569.7 2030.9 757.2 835.3 2030 1174. Memory latencies in nanoseconds - smaller is better (WARNING - may not be correct, check graphs) --------------------------------------------------- Host OS Mhz L1 $ L2 $ Main mem Guesses --------- ------------- ---- ----- ------ -------- ------- base Linux 2.6.16- 2783 0.719 6.5960 110.5 +patch Linux 2.6.16- 2781 0.720 6.5980 111.0 +patch+en Linux 2.6.16- 2784 0.720 6.5970 110.7 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/