From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Daniel P. Berrange" Subject: Re: That xenstored console leak... Date: Mon, 14 Jan 2008 22:59:15 +0000 Message-ID: <20080114225915.GE24703@redhat.com> References: <20080114214848.GB624@totally.trollied.org.uk> <20080114225537.GC624@totally.trollied.org.uk> Reply-To: "Daniel P. Berrange" Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20080114225537.GC624@totally.trollied.org.uk> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: John Levon Cc: xen-devel@lists.xensource.com, Jim Fehlig List-Id: xen-devel@lists.xenproject.org On Mon, Jan 14, 2008 at 10:55:37PM +0000, John Levon wrote: > On Mon, Jan 14, 2008 at 09:54:50PM +0000, Keir Fraser wrote: > > > >> Yes, device controllers clean up by deleting /vm//path/to/device. This > > >> aliases with the new domain's device information (because they're really the > > >> same vm) and so when the old domain is cleaned up the new domain loses > > >> information. Disambiguating with an extra level of indirection seemed the > > >> simplest fix for this. I'm not sure why this leads to xenstore leaks. > > >> > > >> When a domain is finally garbage collected in xend, perhaps we should delete > > >> its entire /vm//? That would seem a nice and reasonable > > >> catch-all. > > > > > > The lack of the latter explains the former - because each instance has a > > > unique /vm path, there's nothing that ever cleans up the older path > > > contents (image etc.). Right? > > > > I don't understand what you mean. There's no code to delete the entire /vm > > path, regardless of whether the path is /vm// or /vm/- > > (I'm pretty sure). > > The old code re-used the same /vm// path, so there was no leak. > The new code creates a completely new /vm/- path, leaking the > old one (/vm/-). Yes, I noticed that too - its rather peculiar - the idea of the /vm/ hierarchy was that it was persistent for any individual VM, across creation attempts. If we append on the path each time it ceases to be persistent and we might as well just kill off /vm and use /local/ for everything. Dan. -- |=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 -=| |=- Perl modules: http://search.cpan.org/~danberr/ -=| |=- Projects: http://freshmeat.net/~danielpb/ -=| |=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 -=|