> -----Original Message----- > From: xen-devel-boun...@lists.xen.org [mailto:xen-devel- > boun...@lists.xen.org] On Behalf Of George Shuklin > Sent: 24 January 2013 11:46 > To: Zoltan Kiss > Cc: 'xen-de...@lists.xen.org'; Dave Scott; Ian Campbell; xen- > a...@lists.xen.org > Subject: Re: [Xen-devel] driver domain crash and reconnect handling > > > >> I expect the outage due to the proto-suspend is dwarfed by the outage > >> caused by a backend going away for however long it takes to notice, > >> rebuild, reset the hardware, etc etc. > > Indeed, probably the backend restoration would take at least 5 > > seconds. Compared to that, the suspend-resume and the frontend device > > reinit is much shorter. > > Probably in storage driver domains it's better to suspend the guest > > immediately when the backend is gone, as the guest can easily crash if > > the block device is inaccessible for a long time. In case of network > > access, this isn't such a big problem. > > > > > Some notes about guest suspend during IO. > > I tested that way for storage reboot (pause all domains, reboot ISCSI storage > and resume every domain). If pause is short (less that 2 minutes), guest can > survive. If pause is longer than 2 minutes, guests in state of waiting for io > completion, detects IO timeout after resuming and cause IO error on virtual > block devices. (PV). >
To be clear here: do you mean you *paused* and then unpaused the VMs, or *suspended* and then resumed the VMs? I suspect you mean the former. Paul _______________________________________________ Xen-api mailing list Xen-api@lists.xen.org http://lists.xen.org/cgi-bin/mailman/listinfo/xen-api
