Re: [pve-devel] [PATCH V2 qemu-server 1/2] enable balloon free-page-reporting

["DERUMIER, Alexandre" <Alexandre.DERUMIER@groupe-cyllene.com>]

Hi Thomas,

any news about this one ?

if you want to enable it by default, I'm doing it in the v1 of the
patch
https://lists.proxmox.com/pipermail/pve-devel/2022-March/051881.html


Also, I have send v2 for bridge no-learning to handle the nolearning

pve-network : fix bridge-disable-mac-learning
https://lists.proxmox.com/pipermail/pve-devel/2022-March/052205.html

[PATCH V2 pve-container 0/1] add disable bridge learning feature 
https://lists.proxmox.com/pipermail/pve-devel/2022-March/052206.html

[PATCH V2 qemu-server 0/3] add disable bridge learning feature  
https://lists.proxmox.com/pipermail/pve-devel/2022-March/052210.html



not related to nolearning but rebased :

[PATCH V2 pve-common 0/1] network: tap_plug: fix mtu bugs 
https://lists.proxmox.com/pipermail/pve-devel/2022-March/052213.html


Also some other pending patches:

[pve-devel] [PATCH pve-docs 0/1] bgp/evpn improvements  
https://lists.proxmox.com/pipermail/pve-devel/2022-February/051710.html
---> updated doc with last sdn changes (already in gui && pve-network)


close #2949: add virtio-mem support
https://lists.proxmox.com/pipermail/pve-devel/2022-March/051955.html
---> need opinion about the implementation




(BTW, I'm still working on pveha balancing, I'll made big rework with
new algorithms. I'll send patchs next month for review)




Le mercredi 16 mars 2022 à 20:32 +0100, alexandre derumier a écrit :
> Le mercredi 16 mars 2022 à 18:48 +0100, Thomas Lamprecht a écrit :
> > On 06.03.22 13:46, Alexandre Derumier wrote:
> > > Allow balloon device  driver to report hints of guest free pages
> > > to
> > > the host,
> > > for auto memory reclaim
> > > 
> > > https://antiphishing.cetsi.fr/proxy/v3?i=WjB4M1dJWGJJMnNGTHV5MuAP
> > > Dw
> > > EdQko7KGyaWIIeme0&r=Skk2OVhvdXl2cm1uOWJtRKZfDro27Y-
> > > CXDQsnaz4_yALcilBfMoOADH4vBnleGIe&f=M2FwZHlGNnU1aUlkc09ZNN_YvBMHD
> > > OR
> > > QlhAYZyYtaZUztHfYUKPa_DyZ9e1ZULhe&u=https%3A//lwn.net/Articles/75
> > > 94
> > > 13/&k=CXOq
> > > https://antiphishing.cetsi.fr/proxy/v3?i=WjB4M1dJWGJJMnNGTHV5MuAP
> > > Dw
> > > EdQko7KGyaWIIeme0&r=Skk2OVhvdXl2cm1uOWJtRKZfDro27Y-
> > > CXDQsnaz4_yALcilBfMoOADH4vBnleGIe&f=M2FwZHlGNnU1aUlkc09ZNN_YvBMHD
> > > OR
> > > QlhAYZyYtaZUztHfYUKPa_DyZ9e1ZULhe&u=https%3A//events19.linuxfound
> > > at
> > > ion.org/wp-content/uploads/2017/12/KVMForum2018.pdf&k=CXOq
> > > Signed-off-by: Alexandre Derumier <aderumier@odiso.com>
> > > ---
> > >  PVE/QemuServer.pm | 4 +++-
> > >  1 file changed, 3 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/PVE/QemuServer.pm b/PVE/QemuServer.pm
> > > index 42f0fbd..a9e86b3 100644
> > > --- a/PVE/QemuServer.pm
> > > +++ b/PVE/QemuServer.pm
> > > @@ -3846,7 +3846,9 @@ sub config_to_command {
> > >      # enable balloon by default, unless explicitly disabled
> > >      if (!defined($conf->{balloon}) || $conf->{balloon}) {
> > >         my $pciaddr = print_pci_addr("balloon0", $bridges, $arch,
> > > $machine_type);
> > > -       push @$devices, '-device', "virtio-balloon-
> > > pci,id=balloon0$pciaddr";
> > > +       my $ballooncmd = "virtio-balloon-
> > > pci,id=balloon0$pciaddr";
> > > +       $ballooncmd .= ",free-page-reporting=on" if
> > > min_version($machine_version, 6, 2);
> > 
> > do we even need to guard this behind 6.2 machine version, as I
> > tried
> > to add it
> > on a running host and migrations in both directions went just fine
> > with a windows
> > 10 VM.
> > 
> > Asking mostly because we already have QEMU 6.2 available publicly
> > on
> > pvetest and
> > use it also for some infrastructure of ours, so if it really would
> > be
> > breaking
> > we'd need to use our separate qemu-version independent machine bump
> > mechanism
> > (+pve1).
> 
> > 
> > But it seems that its not required, or did you find that it can
> > indeed break live
> > migration? fwiw, for us is really only forward migration, from vm
> > without reporting
> > enabled to vm with reporting enabled, relevant.
> > 
> > > +       push @$devices, '-device', $ballooncmd;
> > >      }
> > >  
> > >      if ($conf->{watchdog}) {
> > 
> > 
> 
> 
> oh , sorry, I thinked that 6.2 was not yet pubicly available.
> 
> From my tests:
> a already booted vm without the balloon freepage option enabled --->
> migrating to new vm with balloon freepage option enabled : works
> 
> Then failback it to previous node : works
> 
> 
> But starting a new vm with the option enabled then migrate it to a
> new
> vm withtout the option:
> 
> migration die on resume.
> 
> 2022-03-16 20:28:30 average migration speed: 1.5 GiB/s - downtime 30
> ms
> 2022-03-16 20:28:30 migration status: completed
> 2022-03-16 20:28:30 ERROR: tunnel replied 'ERR: resume failed - VM
> 104
> not running' to command 'resume 104'
> 2022-03-16 20:28:39 ERROR: migration finished with problems (duration
> 00:00:18)
> TASK ERROR: migration problems
> 
> 
> If think this is because guest kernel balloon driver enabled it at
> boot
> only.
> 
> 
> Note that I don't think that current windows drivers already support
> it
> (I have looked at the source code, so even if the option is enabled
> at
> qemu level, it don't do nothing inside windows.
> So I think that migration will works in both direction with windows
> vms.
> 
> 
> 
>