[Spice-devel] spice performance tweaking

[Frediano Ziglio]

I saw you are using CentOS 7. I built the package with RHEL 7 (they are binary compatible). 
About the testing just which normal usage you should see improvements in bandwidth and 
reactivity. 

Changes from current CentOS package: 
- used a newer version, there are couple of changes that decrease latency; 
- additional patches to improve bandwidth usage (for small drawing this should decrease 
bandwidth usage by a 15-20%); 
- additional patch to decrease a bandwidth limitation due to a peculiar half-duplex usage 
of spice protocol (this is clearly visible with high latency connections); 
- additional patch to decrease packet fragmentation due to TCP_NODELAY usage. 

Alternatively would be helpful for us to get a local reproduction of the problem. 
OpenVPN configuration files would be helpful (we don't need any security 
detail like keys, ip, host or system names, just to understand the type of VPN, 
encryption parameters, compression, additional latency introduced and so on). 

The fact that you are not able to get a record from the guest means that the QXL 
(guest <-> server) protocol how the spice-server is handling guest command is 
fine. The fact that on the client you can see clearly such slowness is due to spice 
protocol, the connection/vpn, some spice-server implementation and possibly 
client implementation too. Unfortunately too much stuff to be able to point the 
finger to one of them. 
I tried some test and did this: 
- opened task manager on Windows 7; 
- switched to performance tab; 
- maximized task manager; 
- double clicked on CPU usage to get only CPU usage and history. 
When CPU usage change I can see the flickering on CPU usage but not on 
the history graphs. It this the kind of flickering you are noticing? 

Frediano 

> For which distro is that package ?
> Centos 7.2 ? rhel7.3beta or fedora24 ?

> Rob Verduijn

> 2016-09-14 15:59 GMT+02:00 Frediano Ziglio < fziglio at redhat.com > :

> > Could you test at least? Would be very helpful. We could then backport some
> > improvements.
> 

> > Frediano
> 

> > > thanx,I'll stick with the centos packages,
> > 
> 

> > > I need a very good reason before I start using beta packages.
> > 
> 
> > > And a nice to have feature is not one of them.
> > 
> 

> > > Also I dug in to the openvpn tweaks and it seems that all of them are
> > > related
> > > to udp tunnels.
> > 
> 
> > > Performance is sadly rather low when you have to use tcp (like me)
> > > because
> > > the firewall is managed by a third party.
> > 
> 

> > > Rob Verduijn
> > 
> 

> > > 2016-09-14 15:49 GMT+02:00 Frediano Ziglio < fziglio at redhat.com > :
> > 
> 

> > > > > Hello,
> > > > 
> > > 
> > 
> 

> > > > > I'm trying to improve my spice performance on a kvm host/guest.
> > > > 
> > > 
> > 
> 
> > > > > It's currently rather slow and I can see screens beeing build up, and
> > > > > delays
> > > > > when draging windows.
> > > > 
> > > 
> > 
> 

> > > > > It's being tunneled through openvpn, which is set to use tcp.
> > > > 
> > > 
> > 
> 
> > > > > tcp required because of the firewall which is maintained by 3rd
> > > > > party.
> > > > 
> > > 
> > 
> 

> > > > > I have full access to the kvm host, kvm guest and openvpn server.
> > > > 
> > > 
> > 
> 

> > > > > Have you got any tips so that I can improve spice performance ?
> > > > 
> > > 
> > 
> 
> > > > > I alrready am running tuned with the virtual-guest profile for guests
> > > > > and
> > > > > host profile for the host.
> > > > 
> > > 
> > 
> 
> > > > > All systems are runnning CentOS 7
> > > > 
> > > 
> > 
> 

> > > > > Any tips for :
> > > > 
> > > 
> > 
> 
> > > > > - the KVM host ?
> > > > 
> > > 
> > 
> 
> > > > > - the KVM guest ?
> > > > 
> > > 
> > 
> 
> > > > > - the openvpn server ?
> > > > 
> > > 
> > 
> 

> > > > > Cheers
> > > > 
> > > 
> > 
> 
> > > > > Rob Verduijn
> > > > 
> > > 
> > 
> 

> > > > Hi,
> > > 
> > 
> 
> > > > can you try version at https://www.datafilehost.com/d/b07f008e ?
> > > 
> > 
> 

> > > > The sha1 hash (please check it) is
> > > > 0e2191c363e109475aeb2bff401e699f0a07a795.
> > > 
> > 
> 

> > > > Be prepare for the rollback, it's not a version meant for production
> > > > usage.
> > > 
> > 
> 

> > > > Frediano
> > > 
> > 
> 
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.freedesktop.org/archives/spice-devel/attachments/20160915/69fee604/attachment-0001.html>