From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from dan.rpsys.net ([93.97.175.187]) by linuxtogo.org with esmtp (Exim 4.72) (envelope-from ) id 1R9abh-0004mM-Hf for openembedded-core@lists.openembedded.org; Fri, 30 Sep 2011 12:46:17 +0200 Received: from localhost (dan.rpsys.net [127.0.0.1]) by dan.rpsys.net (8.14.2/8.14.2/Debian-2build1) with ESMTP id p8UAl9La011467; Fri, 30 Sep 2011 11:47:10 +0100 X-Virus-Scanned: Debian amavisd-new at dan.rpsys.net Received: from dan.rpsys.net ([127.0.0.1]) by localhost (dan.rpsys.net [127.0.0.1]) (amavisd-new, port 10024) with LMTP id qcCtBYONbvZf; Fri, 30 Sep 2011 11:47:09 +0100 (BST) Received: from [192.168.1.40] (tim [93.97.173.237]) (authenticated bits=0) by dan.rpsys.net (8.14.2/8.14.2/Debian-2build1) with ESMTP id p8UAIi1q010279 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT); Fri, 30 Sep 2011 11:19:46 +0100 From: Richard Purdie To: McClintock Matthew-B29882 , Patches and discussions about the oe-core layer Date: Fri, 30 Sep 2011 11:12:18 +0100 In-Reply-To: References: <1317143228.26109.203.camel@ted> X-Mailer: Evolution 3.1.91- Message-ID: <1317377605.12332.140.camel@ted> Mime-Version: 1.0 Subject: Re: Build Times and Performance - Discussion + new ideas X-BeenThere: openembedded-core@lists.openembedded.org X-Mailman-Version: 2.1.11 Precedence: list Reply-To: Patches and discussions about the oe-core layer List-Id: Patches and discussions about the oe-core layer List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 30 Sep 2011 10:46:18 -0000 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit On Fri, 2011-09-30 at 01:11 +0000, McClintock Matthew-B29882 wrote: > On Tue, Sep 27, 2011 at 12:07 PM, Richard Purdie > wrote: > > https://wiki.yoctoproject.org/wiki/Build_Performance > > > > As detailed there I've setup a partition formatted with ext4 with no > > journal, no barriers and most importantly a long commit time. The intent > > here is to allow things to exist in memory and not block on disk IO. > > Can you comment on how much these settings effect build times vs. > saying running on ext3 which our build server happens to be using? I don't have absolute numbers but there are the following performance limiting factors: - journal - turned off means faster but more data risk - ext4 has extents (which if nothing else allow deletion of build directories faster). I suspect these are a big win for us given how much direct file writing we do during unpack - noatime changes - reduces amount of writes needed - commit time changes - not forced to only keep 5 seconds of data in memory maximum so less process blocking on IO. You can do some of these things on ext3 (or just enable the features on your existing ext3 disk and start using them, you don't need to reformat). If the disk is your system and build disk, I'd get more worried and probably not recommend the changes. I'd recommend a separate build disk where at all possible. Cheers, Richard