From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ian Campbell Subject: Re: [PATCH OSSTEST v1] ap-fetch-version: Arrange for osstest merges from upstream to be stable Date: Wed, 8 Jul 2015 16:26:42 +0100 Message-ID: <1436369202.23508.68.camel@citrix.com> References: <1435916434-19305-1-git-send-email-ian.campbell@citrix.com> <21917.16513.160656.326376@mariner.uk.xensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <21917.16513.160656.326376@mariner.uk.xensource.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Ian Jackson Cc: xen-devel@lists.xen.org List-Id: xen-devel@lists.xenproject.org On Wed, 2015-07-08 at 16:23 +0100, Ian Jackson wrote: > Ian Campbell writes ("[PATCH OSSTEST v1] ap-fetch-version: Arrange for osstest merges from upstream to be stable"): > > If a downstream osstest instance has nothing to test it its local > > pretest then it will attempt to merge from the upstream instance. If > > this fails then it will try again and again generating a new merge > > commit each time, even if upstream has not moved. > > > > It is desirable that these merges instead be stable i.e. the same if > > the inputs have not changed. This is good for potential bisection > > attempts, history reporting/mining as well as just being sensible. > > > > Here we arrange for this by recording the last merge "epoch" (being > > the first merge of the current input branches) in a new branch > > "merge-epoch" in the local testing.git and comparing our fresh merge > > against it. > > > > If the tree and parents are the same then the merge is effectively > > identical (it may/will differ in the date) and we reuse the epoch > > merge. > > > > If they new merge does not match then something has changed (i.e. > > upstream has moved on) and so we take the new merge and establish a > > new epoch. > > > > Signed-off-by: Ian Campbell > > Acked-by: Ian Jackson Thanks. I've put this into the Cambridge instance's pretest, and will send a pull request to merge back the result when it has baked there. Ian.