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=-4.5 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 DABF92022A for ; Fri, 28 Oct 2016 06:39:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755883AbcJ1GjF (ORCPT ); Fri, 28 Oct 2016 02:39:05 -0400 Received: from mail-oi0-f52.google.com ([209.85.218.52]:35477 "EHLO mail-oi0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751058AbcJ1GjE (ORCPT ); Fri, 28 Oct 2016 02:39:04 -0400 Received: by mail-oi0-f52.google.com with SMTP id i127so104133285oia.2 for ; Thu, 27 Oct 2016 23:39:04 -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=0Xorp1l2ZJPRF0443WYwtWt1AAfJD4LbAdRA0hMguV4=; b=YzEjyIqGvVr88MPZSjri56zxUQLyOsFDuWNlrRwIgO4b4NTODjbDBwhIsCzr79aZH+ EiNsf0SyPUJxWJ5/le9ujp/leM+50Jy5zeAbp3i/uojjcgOOmJ8yqkNSABd077DiXJkL j94uDJGNJJ6RS4I9D9UiF3EBaL3ymJ6sAbfve9HEyqzzYGOHO39sOFikzzoM9ulQVJwq wfIMXSSOsiUklLo4csn8JH8+cb/R6xzE5LAqLCiyGv9QesrnM6VVX6DvBynjz4LE0XSG qCVYXQO1FFbCtJoqVoxLY61tqn/Por2K6YttVx3MHBzcHWonRxW1SD79E5EwN+7Zjg3n ELQQ== 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=0Xorp1l2ZJPRF0443WYwtWt1AAfJD4LbAdRA0hMguV4=; b=EbA5DwiMIYGkiZILNAbHqnUUmWl3Gzev0F3TD1mw5EpTjZ+Q6Lx/UPfHSTkOMVq2ON HMT1dQUTcPO4t1+6Jxr+80+41hhR3s3gq3pVtMGTcW9leDyRgWLzujM08QEtJOmke51O z2jgEvHTzNIMUUK/TV441F4vWG5HB62rKANyFZ98KJtExm1phnh9dmpmnD4HtDAzBsUn VtHkOoQNMeFqPScQflmO0v42vyphi5+MarorCasGf+6pjRuCkJxHEaTFj7tMfp6HJeNg m0rp5Ajd3a4cbrMGlfvuVueUbWorNbpzTf8q0E2qjvgywnAcF9Fo8A4oaM2kgFJGgMkH G5dQ== X-Gm-Message-State: ABUngvfnDX69caSTwfqxVKe/JSWe5pZmtoxiLovYP3xB/SPSZWWbOo5ANcMdAadxKM6NmscOIgT6T7WylyXK1Q== X-Received: by 10.107.59.6 with SMTP id i6mr10104887ioa.176.1477636743632; Thu, 27 Oct 2016 23:39:03 -0700 (PDT) MIME-Version: 1.0 Received: by 10.64.164.102 with HTTP; Thu, 27 Oct 2016 23:38:32 -0700 (PDT) In-Reply-To: <20161027204129.GA21619@starla> References: <20161027204129.GA21619@starla> From: Duy Nguyen Date: Fri, 28 Oct 2016 13:38:32 +0700 Message-ID: Subject: Re: Drastic jump in the time required for the test suite To: Eric Wong Cc: 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 28, 2016 at 3:41 AM, Eric Wong wrote: > Johannes Schindelin wrote: >> I know you are a fan of testing things thoroughly in the test suite, but I >> have to say that it is getting out of hand, in particular due to our >> over-use of shell script idioms (which really only run fast on Linux, not >> a good idea for a portable software). > > How much effort would it take to optimize a /bin/sh? > > Would replacing uses of fork+execve posix_spawn be fast and > portable enough? > > Even on Linux, performance sucks for me. I've been hoping dash > can use posix_spawn (or using vfork directly) to see if that can > help things. Busybox hush uses vfork.on no-mmu builds. You could try it out. I don't know how complete it is though. -- Duy