From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Keeping Subject: Re: "git grep" parallelism question Date: Mon, 29 Apr 2013 19:08:57 +0100 Message-ID: <20130429180857.GK472@serenity.lan> References: <7vr4hxw2mp.fsf@alter.siamese.dyndns.org> <7vip39w14d.fsf@alter.siamese.dyndns.org> <20130429161814.GJ472@serenity.lan> <877gjldxid.fsf@hexa.v.cablecom.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Ramkumar Ramachandra , Linus Torvalds , Junio C Hamano , Git Mailing List To: Thomas Rast X-From: git-owner@vger.kernel.org Mon Apr 29 20:09:15 2013 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 1UWsVm-0001HM-K6 for gcvg-git-2@plane.gmane.org; Mon, 29 Apr 2013 20:09:14 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758077Ab3D2SJJ (ORCPT ); Mon, 29 Apr 2013 14:09:09 -0400 Received: from coyote.aluminati.org ([72.9.247.114]:53603 "EHLO coyote.aluminati.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757190Ab3D2SJI (ORCPT ); Mon, 29 Apr 2013 14:09:08 -0400 Received: from localhost (localhost [127.0.0.1]) by coyote.aluminati.org (Postfix) with ESMTP id 17C91606505; Mon, 29 Apr 2013 19:09:08 +0100 (BST) X-Virus-Scanned: Debian amavisd-new at caracal.aluminati.org X-Spam-Flag: NO X-Spam-Score: -0.999 X-Spam-Level: X-Spam-Status: No, score=-0.999 tagged_above=-9999 required=6.31 tests=[ALL_TRUSTED=-1, URIBL_BLOCKED=0.001] autolearn=ham Received: from coyote.aluminati.org ([127.0.0.1]) by localhost (coyote.aluminati.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 0Bc3RfvLc-jo; Mon, 29 Apr 2013 19:09:07 +0100 (BST) Received: from serenity.lan (mink.aluminati.org [10.0.7.180]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by coyote.aluminati.org (Postfix) with ESMTPSA id 10E4960657C; Mon, 29 Apr 2013 19:08:59 +0100 (BST) Content-Disposition: inline In-Reply-To: <877gjldxid.fsf@hexa.v.cablecom.net> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: On Mon, Apr 29, 2013 at 08:04:10PM +0200, Thomas Rast wrote: > John Keeping writes: > > > On Mon, Apr 29, 2013 at 07:35:01PM +0530, Ramkumar Ramachandra wrote: > >> On a related note, one place that IO parallelism can provide massive > >> benefits is in executing shell scripts. Accordingly, I always use the > >> following commands to compile and test git respectively: > >> > >> make -j 8 CFLAGS="-g -O0 -Wall" > >> make -j 8 DEFAULT_TEST_TARGET=prove GIT_PROVE_OPTS="-j 16" test > >> > >> i.e. always use 8 threads when the task is known to be CPU intensive, > >> and always use 16 threads when the task is known to be IO intensive. > > > > On this tangent, I recently added a TEST_OUTPUT_DIRECTORY line to my > > config.mak which points into a tmpfs mount. Keeping all of the test > > repositories in RAM makes the tests significantly faster for me and > > works nicely when you have the patches in jk/test-output (without those > > patches the individual tests work but the reporting of aggregate results > > doesn't). > > But that's been possible for quite some time now, using --root, or am I > missing something? No, I was the one missing something (--root to be precise). But with TEST_OUTPUT_DIRECTORY you also get the result files in your temporary location, not just the trash directory.