Hi! Is it possible that xl needs more memory than xm? Does xl log somewhere how much memory is free and how much it does want? xl create -c <guest.conf> Parsing config file <guest.conf> failed to free memory for the domain xm create -c <guest.conf> [guest boot messages] Christoph -- ---to satisfy European Law for business letters: Advanced Micro Devices GmbH Einsteinring 24, 85609 Dornach b. Muenchen Geschaeftsfuehrer: Alberto Bozzo, Andrew Bowd Sitz: Dornach, Gemeinde Aschheim, Landkreis Muenchen Registergericht Muenchen, HRB Nr. 43632 _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
On Fri, 5 Nov 2010, Christoph Egger wrote:> > Hi! > > Is it possible that xl needs more memory than xm? > Does xl log somewhere how much memory is free and how much it does want? > > xl create -c <guest.conf> > Parsing config file <guest.conf> > failed to free memory for the domain > > xm create -c <guest.conf> > [guest boot messages] >That''s because of freemem-slack: a basic amount of memory left free on the system otherwise memory allocation for new VMs fails. It is calculated using the amount of free memory at boot time, assuming that dom0 was booted using all the memory in the system. If you boot dom0 passing dom0_mem to xen, then you have to disable autoballooning (autoballoon=0 in /etc/xen/xl.conf). Given the other bug you reported on libxl__fill_dom0_memory_info, I suspect that the freemem-slack value might be wrong on your system. On the other hand if your configuration is correct, we might have to lower the maximum value of freemem-slack that currently is 15% of the total memory in the system. _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Stefano Stabellini writes ("Re: [Xen-devel] xl vs. xm: memory
consumption"):> It is calculated using the amount of free memory at boot time, assuming
> that dom0 was booted using all the memory in the system.
Perhaps it would be worth spotting if freemem_slack is very large and
issuing a warning ? That would help spot this particular
configuration error which I suspect may become common.
Ian.
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On Wed, 10 Nov 2010, Ian Jackson wrote:> Stefano Stabellini writes ("Re: [Xen-devel] xl vs. xm: memory consumption"): > > It is calculated using the amount of free memory at boot time, assuming > > that dom0 was booted using all the memory in the system. > > Perhaps it would be worth spotting if freemem_slack is very large and > issuing a warning ? That would help spot this particular > configuration error which I suspect may become common.I agree. Currently we limit freemem_slack to 15% of the system memory, maybe we should lower that limit? _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel