Re: [Xen-devel] [win-pv-devel] Question about windows domU long boot time in xen and help for update libxl virtio patch (for a test)

[Paul Durrant <Paul.Durrant@xxxxxxxxxx>]

> -----Original Message-----
> From: win-pv-devel-bounces@xxxxxxxxxxxxxxxxxxxx [mailto:win-pv-devel-
> bounces@xxxxxxxxxxxxxxxxxxxx] On Behalf Of Fabio Fantoni
> Sent: 08 May 2015 15:54
> To: xen-devel; win-pv-devel@xxxxxxxxxxxxxxxxxxxx
> Cc: Anthony Perard; Wei Liu; Ian Campbell; Stefano Stabellini
> Subject: [win-pv-devel] Question about windows domU long boot time in
> xen and help for update libxl virtio patch (for a test)
> 
> In latest years hvm domUs support and performance was increased but
> windows boot time is still too long.
> I tried out all sort of combinations (without pv, with old gplpv and new
> winpv, with vnc, spice or without both, with different vgas and many
> other options) with same result: strange long boot time (before arrive
> to user login).
> On kvm (trying with same qemu/seabios versions, qdisk with raw ecc...)
> instead for example the boot time is faster and similar to the phisical
> pc one with same vcpu ram ecc as assigned.
> Is there something that need to be improved/fixed in windows pv drivers
> or xen?
> 

Which version of QEMU are you using. I tend to use upstream, but I see a *very* 
long pause between the end of firmware logging and sampling the viridian cpuid 
leaves (which is generally the next thing to cause some logging) so my 
suspicion is that the int13 handling in seabios is probably the culprit. That's 
only a hunch, but using rombios and qemu trad is quite a lot faster.

Once the kernel starts to boot I see no significant delays. PV drivers are not 
wonderfully fast to start up as the xenstore state dance does take a while. It 
is somewhat unavoidable though.

  Paul

> I tried to narrow down my search trying with virtio disk on xen but I
> was unable to have libxl patch working.
> I taken very old Wei Liu patch from here:
> http://downloads.xen.org/Wiki/VirtioOnXen/libxl-virtio-support.patch
> 
> And I tried to adapt it but there is something that I not understand and
> causing the build fails:
> libxl.c:2339:32: error: LIBXL__DEVICE_KIND_VIRTIO undeclared (first use
> in this function)
> 
> Here the path I updated and tried failing, I did only disks part (nic
> need only model change in xl.cfg FWIK):
> https://github.com/Fantu/Xen/commit/783c1739df3a87689ab8c152632b2493
> 34d92f0a
> 
> Can someone help me to complete/fix it please?
> 
> 
> Thanks for any reply and sorry for my bad english.
> 
> 
> _______________________________________________
> win-pv-devel mailing list
> win-pv-devel@xxxxxxxxxxxxxxxxxxxx
> http://lists.xenproject.org/cgi-bin/mailman/listinfo/win-pv-devel

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel