From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay1.mentorg.com ([192.94.38.131]) by linuxtogo.org with esmtp (Exim 4.72) (envelope-from ) id 1QV2qP-0006bV-2B for openembedded-core@lists.openembedded.org; Fri, 10 Jun 2011 16:37:53 +0200 Received: from svr-orw-exc-10.mgc.mentorg.com ([147.34.98.58]) by relay1.mentorg.com with esmtp id 1QV2n9-00068O-Qb from Tom_Rini@mentor.com for openembedded-core@lists.openembedded.org; Fri, 10 Jun 2011 07:34:31 -0700 Received: from SVR-ORW-FEM-03.mgc.mentorg.com ([147.34.97.39]) by SVR-ORW-EXC-10.mgc.mentorg.com with Microsoft SMTPSVC(6.0.3790.4675); Fri, 10 Jun 2011 07:30:13 -0700 Received: from [172.30.36.148] (147.34.91.1) by svr-orw-fem-03.mgc.mentorg.com (147.34.97.39) with Microsoft SMTP Server id 14.1.289.1; Fri, 10 Jun 2011 07:34:30 -0700 Message-ID: <4DF22B70.2090002@mentor.com> Date: Fri, 10 Jun 2011 07:34:24 -0700 From: Tom Rini Organization: Mentor Graphics Corporation User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.2.17) Gecko/20110424 Lightning/1.0b2 Thunderbird/3.1.10 MIME-Version: 1.0 To: References: <4DE850E8.2050701@windriver.com> <4DF14BE9.7080704@intel.com> <4DF15C93.7090606@mentor.com> <4DF18783.6050303@gmail.com> In-Reply-To: <4DF18783.6050303@gmail.com> X-Enigmail-Version: 1.1.1 X-OriginalArrivalTime: 10 Jun 2011 14:30:13.0594 (UTC) FILETIME=[E906EBA0:01CC277A] Subject: Re: [Yocto] The design document for ccache-native 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, 10 Jun 2011 14:37:53 -0000 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit On 06/09/2011 07:54 PM, Khem Raj wrote: > On 06/09/2011 04:51 PM, Tom Rini wrote: >> On 06/09/2011 03:40 PM, Saul Wold wrote: >>> On 06/02/2011 08:11 PM, wenzong fan wrote: >>>> Hi Folks, >>>> >>>> Please help me to review the design document for ccache-native, and >>>> I also have two questions about it, any answers or suggestions are >>>> appreciated. >>>> >>>> * Feature name: ccache-native >>>> Priority: P3; M2 >>>> Owner: Wenzong Fan >>>> Summary: Integrate ccache-native to yocto >>>> >>>> * Description: >>>> Bitbake supports the 'CCACHE Mechanism', but 'ccache' hasn't been >>>> included by poky/yocto, just add it as a native tool. >>>> >>>> * Usage: >>>> Build ccache as a native tool by default and enable it for speeding >>>> target packages build. >>>> >>>> * Implementation: >>>> 1) Copy bb file from OE upstream to: >>>> meta/recipes-devtools/ccache/ >>>> >>>> 2) Update bb file to get the latest ccache_3.1.5 and split the single >>>> bb file to: >>>> 'ccache_3.1.5.bb', 'ccache.inc' >>>> >>>> 3) Enable ccache in the native tools building. >>>> >>> You will need to have it be a dependency pretty early on in the build. >>> Additionally, this is a bit a new part to this task, we want to have the >>> default CCACHE_DIR for the build default to a directory in TMPDIR >>> instead of the user's home directory. This will mean setting an >>> environment variable somewhere early also. >> >> Can we instead veto ccache and remove it from the bitbake docs? I can't >> count the number of times I've run into what I can only imagine are >> ccache conflicts to explain why a random build failure with ccache in >> use. > > It works on some hosts somewhat reliably and is unpredictable on some as > you say. I think keeping it optional is probably the right thing but > making it default may not be a good thing. I'm pretty sure it's not reliable so much as lucky, but shoving the cache somewhere else and making it per-recipe makes me less worried. -- Tom Rini Mentor Graphics Corporation