Re: [pve-devel] [PATCH qemu-server] apply pending changes at vm stop only if the section is not empty

[Oguz Bektas <o.bektas@proxmox.com>]

On Wed, Dec 01, 2021 at 03:10:28PM +0100, Fabian Ebner wrote:
> Am 01.12.21 um 13:00 schrieb Oguz Bektas:
> > we also have the same skipping logic when starting vms. this way we
> > avoid calling 'write_config' when there are no present changes to
> > commit.
> > 
> > Signed-off-by: Oguz Bektas <o.bektas@proxmox.com>
> > ---
> >   PVE/QemuServer.pm | 6 ++++--
> >   1 file changed, 4 insertions(+), 2 deletions(-)
> > 
> > diff --git a/PVE/QemuServer.pm b/PVE/QemuServer.pm
> > index 45b704d..1379f33 100644
> > --- a/PVE/QemuServer.pm
> > +++ b/PVE/QemuServer.pm
> > @@ -4998,6 +4998,8 @@ sub vmconfig_delete_or_detach_drive {
> >   sub vmconfig_apply_pending {
> >       my ($vmid, $conf, $storecfg, $errors) = @_;
> > +    return if !scalar(keys %{$conf->{pending}});
> 
> Isn't this part of the patch enough? For the caller while starting a VM you
> mentioned, there is an additional load_config() that is skipped if there are
> no pending changes, but for the two callers below, there is no such benefit.
> They just indicate that any pending changes should be applied, which is fine
> even if there are none.

yes i guess it's alright to keep this part only :) though we could still
avoid the vmconfig_apply_pending call in vm_stop_cleanup completely if
the section is empty anyway. not that it brings much but still it
should be fine..

> 
> > +
> >       my $add_apply_error = sub {
> >   	my ($opt, $msg) = @_;
> >   	my $err_msg = "unable to apply pending change $opt : $msg";
> > @@ -5889,7 +5891,7 @@ sub _do_vm_stop {
> >   		die "VM quit/powerdown failed - got timeout\n";
> >   	    }
> >   	} else {
> > -	    vm_stop_cleanup($storecfg, $vmid, $conf, $keepActive, 1) if $conf;
> > +	    vm_stop_cleanup($storecfg, $vmid, $conf, $keepActive, scalar(keys %{$conf->{pending}})) if $conf;
> 
> Style nit: >100 characters
> 
> >   	    return;
> >   	}
> >       } else {
> > @@ -5920,7 +5922,7 @@ sub _do_vm_stop {
> >   	sleep 1;
> >       }
> > -    vm_stop_cleanup($storecfg, $vmid, $conf, $keepActive, 1) if $conf;
> > +    vm_stop_cleanup($storecfg, $vmid, $conf, $keepActive, scalar(keys %{$conf->{pending}})) if $conf;
> >   }
> >   # Note: use $nocheck to skip tests if VM configuration file exists.
> >