From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-4.1 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,RCVD_IN_DNSWL_HI,RCVD_IN_SORBS_SPAM, RP_MATCHES_RCVD shortcircuit=no autolearn=ham autolearn_force=no version=3.4.0 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id 31E8220986 for ; Fri, 21 Oct 2016 11:04:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932171AbcJULEG (ORCPT ); Fri, 21 Oct 2016 07:04:06 -0400 Received: from mail-it0-f50.google.com ([209.85.214.50]:38315 "EHLO mail-it0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932247AbcJULEF (ORCPT ); Fri, 21 Oct 2016 07:04:05 -0400 Received: by mail-it0-f50.google.com with SMTP id 66so152014646itl.1 for ; Fri, 21 Oct 2016 04:04:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=BfcsPrKzbJSD/uYhLVDi9TaT0J/2Sz3RmKQUzWSmNJY=; b=W3ug4IJDpasGupJttpUbG61OM+h1IoGbJ9+V5gjmYIc+w2zH64z3UWh7asreSMpFNC LWwX55KxYVhumRsBeAkdm+YslULNMR0dYxxFyU0RqZOWtbGqOKVD0f4x1FR76geVeVHq ln2eJPkKt0Pbgc99/mpUZsupbuw1FsbJhBxwBD61m2RzFUw1hn6HCRL5eCfwPROi2vRS eSYGad+/oHuwVIXJa1HU5MjRmMYeU98/KZzg+WErdWVH1v6anRxKeZsuY4ejHpApt1t1 sZRdFaH7BtB5yI2mDHQ18Ecq8CMjK2lZ9d42UlIjsP45OGLFPsCGsCLD3Qob70M17nJf Y/8w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=BfcsPrKzbJSD/uYhLVDi9TaT0J/2Sz3RmKQUzWSmNJY=; b=eR/xSoQj7oeYTdzMBhtPTs9cWjVTWbH2DLpi+Gh1wB3wJXGL7YlVUnI/OnFN0ls9ii A+p5QNFX3mFvjRg7bAtyC+17hgRLWds7vAWd3X3SFBGhoLvWiR8+6z/Q4gNzJS6GvvhB tLFf2PgvE4dPy3MttDRO1J1WgpCPRZ+kUIBv163Ws/pNeov0j1NpO8D2gt7RbpsE4EWD b7Cs+byl4lp2WO7ZUvvt5Uy5KOoeHdCh4BiYTOFvIs7RoF0LVSOHmpI9Jko8ys8G8Axu fORJblNaKsCDofpabKr7zmui8zuCA7iZvk8loiJjp/FKk98E6cCX7dyoJFsgMnRIMB7X S8OQ== X-Gm-Message-State: ABUngvd2YA2FtySbyrimrk3QuE4XE6Ue7Z/Wk9HjH5NBaJ4j6VUrYQWu7omCsTnVF6N4Y01ogdYmrzm1S0jg7Q== X-Received: by 10.107.59.6 with SMTP id i6mr289510ioa.176.1477047843757; Fri, 21 Oct 2016 04:04:03 -0700 (PDT) MIME-Version: 1.0 Received: by 10.64.164.102 with HTTP; Fri, 21 Oct 2016 04:03:32 -0700 (PDT) In-Reply-To: <1476996017.28685.10.camel@kaarsemaker.net> References: <20161020123111.qnbsainul2g54z4z@sigill.intra.peff.net> <1476996017.28685.10.camel@kaarsemaker.net> From: Duy Nguyen Date: Fri, 21 Oct 2016 18:03:32 +0700 Message-ID: Subject: Re: Drastic jump in the time required for the test suite To: Dennis Kaarsemaker Cc: Jeff King , Johannes Schindelin , Junio C Hamano , Git Mailing List Content-Type: text/plain; charset=UTF-8 Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Fri, Oct 21, 2016 at 3:40 AM, Dennis Kaarsemaker wrote: > On Thu, 2016-10-20 at 08:31 -0400, Jeff King wrote: > >> I'm also not entirely convinced that the test suite being a shell script >> is the main culprit for its slowness. We run git a lot of times, and >> that's inherent in testing it. I ran the whole test suite under >> "strace -f -e execve". There are ~335K execs. Here's the breakdown of >> the top ones: > > You're measuring execve's, but fork (well, fork emulation. There's no > actual fork) is also expensive on windows iirc, so subshells add a lot > to this cost. shells fork on piping as well, and redirection and some other construct if I remember correctly (I attempted to port busybox ash to windows and had to find and "fix" all the forks) > That said, strace -eclone says that a 'make test' forks > ~408k times, and while this is significantly more than the amount of > execs in your example, this does include cvs and svn tests and it's > still in the same ballpark. -- Duy