From mboxrd@z Thu Jan 1 00:00:00 1970 From: Junio C Hamano Subject: Re: Parallel checkout (Was Re: 0 bot for Git) Date: Fri, 15 Apr 2016 10:31:39 -0700 Message-ID: References: <20160415095139.GA3985@lanh> <20160415165208.GA17928@sigill.intra.peff.net> Mime-Version: 1.0 Content-Type: text/plain Cc: Christian Couder , Duy Nguyen , Stefan Beller , "git\@vger.kernel.org" , Michael Haggerty To: Jeff King X-From: git-owner@vger.kernel.org Fri Apr 15 19:31:47 2016 Return-path: Envelope-to: gcvg-git-2@plane.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1ar7as-0000Lu-Np for gcvg-git-2@plane.gmane.org; Fri, 15 Apr 2016 19:31:47 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752551AbcDORbn (ORCPT ); Fri, 15 Apr 2016 13:31:43 -0400 Received: from pb-smtp2.pobox.com ([64.147.108.71]:63260 "EHLO sasl.smtp.pobox.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751851AbcDORbm (ORCPT ); Fri, 15 Apr 2016 13:31:42 -0400 Received: from sasl.smtp.pobox.com (unknown [127.0.0.1]) by pb-smtp2.pobox.com (Postfix) with ESMTP id 5F3C713AF4; Fri, 15 Apr 2016 13:31:41 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=pobox.com; h=from:to:cc :subject:references:date:in-reply-to:message-id:mime-version :content-type; s=sasl; bh=UjAQcThT1qbk40IIUoTOii9ILRA=; b=vNct5h HRtVjCk7ZDOFreIHvKTPf4lAigjsVkUSf8/eci8Me6sOf0kZe0+VZuzfaFUI8uup 4crLFoKDEJxZhXtHcDlCT3jE09HFRYv+7GXm8iCsdJriPfsGgfsQG6nAWiqFXIUg dKioDoPtjFjhoAARNnu46OpXaUvrkSZNpEl7g= DomainKey-Signature: a=rsa-sha1; c=nofws; d=pobox.com; h=from:to:cc :subject:references:date:in-reply-to:message-id:mime-version :content-type; q=dns; s=sasl; b=DqY6e0noTaFVSraPrW1Vxd1t2Hh9EXQq qgzcoQ1HvNIioIMIRRwUZ7Y0SUfbWrT6uE640sIZ6eaZ1PCAey76fvqn5GxZ14Jn 6g70s9+JfkKoTwaVOphhB4CtsKVQcgVC7AhMCoz9Xm2KwQmnH2/32qJ4rskLaHS5 cjBUfkHefnU= Received: from pb-smtp2.nyi.icgroup.com (unknown [127.0.0.1]) by pb-smtp2.pobox.com (Postfix) with ESMTP id 579E913AF3; Fri, 15 Apr 2016 13:31:41 -0400 (EDT) Received: from pobox.com (unknown [104.132.0.95]) (using TLSv1.2 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by pb-smtp2.pobox.com (Postfix) with ESMTPSA id A57F413AF1; Fri, 15 Apr 2016 13:31:40 -0400 (EDT) In-Reply-To: <20160415165208.GA17928@sigill.intra.peff.net> (Jeff King's message of "Fri, 15 Apr 2016 12:52:08 -0400") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) X-Pobox-Relay-ID: EA1D8FBC-032F-11E6-9A19-D05A70183E34-77302942!pb-smtp2.pobox.com Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: Jeff King writes: > On Fri, Apr 15, 2016 at 01:18:46PM +0200, Christian Couder wrote: > >> On Fri, Apr 15, 2016 at 11:51 AM, Duy Nguyen wrote: >> > On Fri, Apr 15, 2016 at 12:04:49AM +0200, Christian Couder wrote: >> >> >> >> There is a draft of an article about the first part of the Contributor >> >> Summit in the draft of the next Git Rev News edition: >> >> >> >> https://github.com/git/git.github.io/blob/master/rev_news/drafts/edition-14.md >> > >> > Thanks. I read the sentence "This made people mention potential >> > problems with parallelizing git checkout" and wondered what these >> > problems were. >> >> It may have been Michael or Peff (CC'ed) saying that it could break >> some builds as the timestamps on the files might not always be ordered >> in the same way. > > I don't think it was me. I'm also not sure how it would break a build. Yup, "will break a build" is a crazy-talk that I'd be surprised if you said something silly like that ;-) Last time I checked, I think the accesses to attributes from the convert.c thing was one of the things that are cumbersome to make safe in multi-threaded world.