From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rusty Russell Subject: Re: /proc/xen/xenbus supports watch? Date: Mon, 26 Sep 2005 08:52:07 +1000 Message-ID: <1127688727.9596.3.camel@localhost.localdomain> References: <5d7aca9505090801025f3d5771@mail.gmail.com> <1126945564.29203.116.camel@localhost.localdomain> <1127088661.23870.47.camel@localhost.localdomain> <1127214064.2656.45.camel@localhost.localdomain> <61d8a8d77f6cbe2402b6a05810bd9447@cl.cam.ac.uk> <1127355755.7567.24.camel@localhost.localdomain> <4f7ac507bdbff3eafe3d0aaba1446e41@cl.cam.ac.uk> <1127433079.2722.24.camel@localhost.localdomain> <1127609824.796.28.camel@localhost.localdomain> <4ba3195147df19b9de13bec776083940@cl.cam.ac.uk> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4ba3195147df19b9de13bec776083940@cl.cam.ac.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: Keir Fraser Cc: Andrew Warfield , xen-devel List , Steven Hand , Christian Limpach List-Id: xen-devel@lists.xenproject.org On Sun, 2005-09-25 at 12:09 +0100, Keir Fraser wrote: > How will you handle 'xenstored restart'? You can't really guarantee > that to always happen at opportune moments with no transactions in > flight. Transaction IDs: when you create a transaction instead of returning "OK" it returns an ID (this also helps if later we want multiple transactions at a time on a single connection). If you were in a transaction you EBADF, you simply ask for it back before continuing: this can be done by libxenstore. It's simple enough to implement, because xenstored keeps each transaction in a separate file: it just has to pick up those files again on restart. I'll start sending patches... Cheers, Rusty. -- A bad analogy is like a leaky screwdriver -- Richard Braakman