From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx12-05.smtp.antispamcloud.com (mx12-05.smtp.antispamcloud.com [46.165.232.175]) by mail.openembedded.org (Postfix) with ESMTP id 1FB67770FA for ; Thu, 4 Feb 2016 12:56:51 +0000 (UTC) Received: from 100-208.ftth.onsbrabantnet.nl ([88.159.208.100] helo=TOP-EX01.TOPIC.LOCAL) by mx12.antispamcloud.com with esmtps (TLSv1:AES256-SHA:256) (Exim 4.85) (envelope-from ) id 1aRJSn-0006e0-6a for openembedded-core@lists.openembedded.org; Thu, 04 Feb 2016 13:56:49 +0100 Received: from [192.168.80.121] (192.168.80.121) by TOP-EX01.TOPIC.LOCAL (192.168.10.102) with Microsoft SMTP Server (TLS) id 14.3.224.2; Thu, 4 Feb 2016 13:56:44 +0100 To: References: <56B0AE88.3090103@siemens.com> <1454446338.7421.45.camel@pbcl.net> <46DD8494-2C7E-44B8-8793-12228FD56738@gmail.com> <1454532510.7421.54.camel@pbcl.net> <1454533078.7421.57.camel@pbcl.net> From: Mike Looijmans Organization: TOPIC Message-ID: <56B34A8B.5040405@topic.nl> Date: Thu, 4 Feb 2016 13:56:43 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.4.0 MIME-Version: 1.0 In-Reply-To: X-Originating-IP: [192.168.80.121] X-EXCLAIMER-MD-CONFIG: 9833cda7-5b21-4d34-9a38-8d025ddc3664 X-EXCLAIMER-MD-BIFURCATION-INSTANCE: 0 X-Filter-ID: s0sct1PQhAABKnZB5plbIbbvfIHzQjPVmPLZeVYSu3xU9luQrU+8/8qthi+0Jd/W6KAUC/fjyuDn NXFr4uarw0hD9tOHsAupOgHE9PArDByM+/sFVMoIHnzxJpiwTwAmqWxCevbUegdCrqkn8BN/sbj/ kr1uWvhVMCtfj6/xQtWU2yOX8PQJGjCrFTzGoLEG6qRPWZXLLVCm/J3adcaGPgWdtN4gC2+aLO2h lecrPdUccBIk1Sag4dKiqCrF8eZZT/hdFFgBT9ea6XfhiStFUv0vp5jSjOOm60a9gEPheCAX2ECf 0tidf4f9xbnt4dr3ucE6FVHy9oQcVLiVeDoadp8jI9oH6dGc6edzLFJtSM1o5rQC2VE4ySdZe0mi K6wgOmG6/54gza7q5Za0AFsz6J51OyFNIoaxpS1mXZNdroDmT8QCc9ZpOAxSvIJNEAP1O4I2wVTs obDkZgzKyHvXxNy0HPTmuB9/GAQDSlCp43waKXvNWrRcSD72jROfhu6vZJ0Q4x+0GOxZvoENDONK wZkjGlUCvU6ZAmJB8zrNH9BlxMWrrEY4M+w4AQhbqSGAGfxNlhQyZmS3TgLw2A6IYlwvyVyNd0zt xHpovTZEu2ZhcIWmrxicQkxvc9w0CTELrSOIPpeqwlm2NDGXIJ2x7JRglvLLWVUnqdg6gt3vmJi/ EuhRQ6HZH7TD+UzWkF8W12aoSjUKxdXaKO35Ea/DrU+pok6SWPRM754kFPO4pu4= X-Report-Abuse-To: spam@mx99.antispamcloud.com X-Filter-Fingerprint: IFrWXGses7OKB5S5G8/dJUb3OPwsHaH0Fvg5oXltHd/JUWjZ8+qhjyB23tbDuyLOYL8Ff78gYsez 4Rl08xudmXi4esCQ0R1MchVjt7wblGlvhFgW0MjUMRkF5sMCDfftTXNFDzN17hnrWeZYOJvLq0Ic WjZ+XcEjj/7Pkld0zkmvziDInX9WdMov2kn2yXjdwv61T+KDYyYtREgszdyFwv8IxCB3p/oCKvxr eyISh3JGb7OS5oVgiO+kDxZrVPLz3MmEGC2PrUKqLq5WmHK+Nw== X-Originating-IP: 88.159.208.100 X-SpamExperts-Domain: topic.nl X-SpamExperts-Username: 88.159.208.100 Authentication-Results: antispamcloud.com; auth=pass smtp.auth=88.159.208.100@topic.nl X-SpamExperts-Outgoing-Class: ham X-SpamExperts-Outgoing-Evidence: SB/global_tokens (0.00465254017537) X-Recommended-Action: accept Subject: Re: Default value for FULL_OPTIMIZATION X-BeenThere: openembedded-core@lists.openembedded.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Patches and discussions about the oe-core layer List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 04 Feb 2016 12:56:52 -0000 Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: quoted-printable =EF=BB=BFOn 03-02-16 21:59, Khem Raj wrote: > On Wed, Feb 3, 2016 at 12:57 PM, Phil Blundell wrote: >> On Wed, 2016-02-03 at 12:51 -0800, Khem Raj wrote: >>> On Wed, Feb 3, 2016 at 12:48 PM, Phil Blundell wrote: >>>> On Tue, 2016-02-02 at 22:17 -0800, Khem Raj wrote: >>>>> -pipe does speed up build time so its an optimization. >>>> >>>> How much does it really speed it up by? I seem to recall the effect w= as >>>> fairly negligible, but maybe I am remembering that wrong. >>> >>> it does not create files for intermediate objects so if you have slow >>> media it can be significant >>> but if you have SSDs then it might be diminished. >> >> The files go in /tmp though, right? Even if that isn't a tmpfs, which I >> think it is on almost all systems nowadays, they will almost certainly >> just sit in the buffer cache and never actually get written to the >> disk. > > in systems of this age it should be yet. In the lab, yes. In the real world, the system may be under load. On desktop computers, /tmp= /=20 is usually NOT on tmpfs. At some point, in order to "write" to your filesystem, it will need to read= it=20 first (e.g. to get a free allocation spot). In that cause, the read request= =20 will have to get in line behind the other IO requests in the queue, and it= =20 suddenly might take seconds to perform that simple request. Even on SSD, th= is=20 will happen and give a noticable drop in performance. You might want to run that test while reading your disk (dd if=3D/dev/sda=20 of=3D/dev/null) and see what happens. Kind regards, Mike Looijmans System Expert TOPIC Embedded Products Eindhovenseweg 32-C, NL-5683 KH Best Postbus 440, NL-5680 AK Best Telefoon: +31 (0) 499 33 69 79 E-mail: mike.looijmans@topicproducts.com Website: www.topicproducts.com Please consider the environment before printing this e-mail Visit us at: Embedded World 2016 Germany, Hall 1, stand number 220. Click here to schedule an appointment with us at Embedded World, free ticke= t included http://topicembeddedproducts.com/schedule-an-appointment/