Re: [libvirt] [PATCH] qemu: Try multiple times to open unix monitor socket

On Wed, Jul 15, 2009 at 11:40:42AM +0200, Daniel Veillard wrote: > On Tue, Jul 14, 2009 at 06:22:42PM -0400, Cole Robinson wrote: > > Unlike the pty monitor (which we know exists since we scrape its path from > > stdout), we have no way of knowing that the unix monitor socket should exist/ > > be initialized. As a result, some of my KVM guests randomly fail to start on > > F10 host. > > > > Try to open the unix socket in a 3 second timeout loop. Ignore EACCES (path > > does not exist if a first time run) and ECONNREFUSED (leftover socket from > > a previous run hasn't been removed yet). Fixes things for me. > > It's always a bit annoying to end up with heuristics like this > but if we don't have any other way, okay, ACK I don't like it much either, but this is no worse than what we had todo to find the /dev/pts/XXX path where we waited ina loop for 3 seconds. ACK to this patch Long term we'll need to discuss with QEMU developers to find a better way todo this without needing a timeout. One idea is actually instead of passing a UNIX domain socket path to QEMU, actually create & bind the socket in libvirt and then pass the pre-opened FD to QEMU. This would guarentee that we can instantly connect to the monitor. Of course then the job of waiting passes to the code that sends monitor commands.