Re: [Qemu-devel] [PATCH] Stop VM on ENOSPC error

[Gleb Natapov]

On Wed, Jan 14, 2009 at 06:39:55PM +0000, Jamie Lokier wrote:
> Gleb Natapov wrote:
> > On Wed, Jan 14, 2009 at 04:47:17PM +0000, Jamie Lokier wrote:
> > > Gleb Natapov wrote:
> > > > And repeat last IDE command after VM restart.
> > > 
> > > If there are multiple AIOs in flight when you get ENOSPC, you may need
> > > to repeat all of them.
> > > 
> > IDE does not support multiple outstanding commands. For SCSI that will have
> > to be done though. What my patch is missing is PIO mode support, but this
> > should be easy to add.
> 
> For some reason I imagined IDE with TCQ(sp?), or SATA with NCQ :-)
> 
But we don't support it yet.

> What about multiple IDE controllers.  If the VM is stopped (for any
> reason, not just ENOSPC) and resumed later, do _other_ controllers'
> AIOs in flight need to be replayed?  Are they saved in snapshot state?
> 
I think (not sure) vmstop stops only CPU execution, but all outstanding IOs
will complete.

--
                        Gleb.