From mboxrd@z Thu Jan 1 00:00:00 1970 From: Junio C Hamano Subject: Re: [PATCH] Avoid unnecessary 'lstat()' calls in 'get_stat_data()' Date: Sun, 10 May 2009 11:40:53 -0700 Message-ID: <7v7i0oztqi.fsf@alter.siamese.dyndns.org> References: <7v8wl5613c.fsf@alter.siamese.dyndns.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Git Mailing List To: Linus Torvalds X-From: git-owner@vger.kernel.org Sun May 10 20:41:04 2009 Return-path: Envelope-to: gcvg-git-2@gmane.org Received: from vger.kernel.org ([209.132.176.167]) by lo.gmane.org with esmtp (Exim 4.50) id 1M3DxP-0001Vs-AN for gcvg-git-2@gmane.org; Sun, 10 May 2009 20:41:03 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755756AbZEJSkz (ORCPT ); Sun, 10 May 2009 14:40:55 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755075AbZEJSky (ORCPT ); Sun, 10 May 2009 14:40:54 -0400 Received: from fed1rmmtao104.cox.net ([68.230.241.42]:32868 "EHLO fed1rmmtao104.cox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754051AbZEJSkx (ORCPT ); Sun, 10 May 2009 14:40:53 -0400 Received: from fed1rmimpo02.cox.net ([70.169.32.72]) by fed1rmmtao104.cox.net (InterMail vM.7.08.02.01 201-2186-121-102-20070209) with ESMTP id <20090510184054.URIJ17135.fed1rmmtao104.cox.net@fed1rmimpo02.cox.net>; Sun, 10 May 2009 14:40:54 -0400 Received: from localhost ([68.225.240.211]) by fed1rmimpo02.cox.net with bizsmtp id pugu1b0024aMwMQ04uguuy; Sun, 10 May 2009 14:40:54 -0400 X-Authority-Analysis: v=1.0 c=1 a=FBa1IiYnV70A:10 a=_rGolq_aGIsA:10 a=Z4Rwk6OoAAAA:8 a=VwQbUJbxAAAA:8 a=i7_erqn0K4wXRTdKx20A:9 a=jRKbG0R9RUeJBZH2OfoA:7 a=ZblIstSz65YyIqJSscRUIgNAFHAA:4 a=U62fhAwekXMA:10 a=jbrJJM5MRmoA:10 X-CM-Score: 0.00 User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.2 (gnu/linux) Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: Linus Torvalds writes: > I've found that "make -j64 test" does fairly well, bringing the cost down > to something reasonable. Some of the SVN tests seem to sometimes randomly > fail when done in parallel (I've not tried to debug it, I assume it's > either some SVN bug, or just the test infrastructure having some shared > SVN central repo thing), but it happens rarely enough that even if you > have to run it twice, it's still worth it. > > [ Side note: the success output of "make test" makes it almost impossible > to debug the error cases when you do that "make -j64" thing. Sad. It > would be good to have the tests that fail clearly say exactly what test > failed, because when you run 64 tests at the same time, having "case 9" > fail is almost totally useless information - test 9 of _which_ > testsuite? ] > > I don't generally build docs, but they should run in parallel too, and at > least your fedora build on kernel.org has a nice quad-core machine with > lots of memory, so "-j8" or something is reasonable. Thanks; unfortunately I already do all the tricks known to me, including running make in parallel (I happen to use -j4) and maintaining a separate build farm for each of the branches to avoid recompilation of programs and reformatting docs. However, on a model name : AMD Athlon(tm) 64 X2 Dual Core Processor 3800+ stepping : 1 cpu MHz : 2004.185 cache size : 512 KB with slow IDE disks, optimizing and cheating at the software level goes only so far... For example, a typical cycle I just did looks like this: $ /usr/bin/time Meta/Dothem --pedantic >:all.log 2>&1; tail -n 2 :all.log 2089.15user 1610.16system 45:56.91elapsed 134%CPU (0avgtext+0avgdata 0maxresident)k 220088inputs+3723296outputs (696major+305868883minor)pagefaults 0swaps You have to remember that people use boxes that are a bit slower compared to the boxes you are used to ;-)