Re: [Xen-devel] [PATCH] libxc: try to find last used pfn when migrating

2015-11-30 Thread Juergen Gross
On 30/11/15 10:47, Andrew Cooper wrote: > On 30/11/15 08:17, Juergen Gross wrote: >> On 27/11/15 18:16, Andrew Cooper wrote: >>> On 27/11/15 15:53, Juergen Gross wrote: On 27/11/15 16:33, Wei Liu wrote: > On Fri, Nov 27, 2015 at 03:50:53PM +0100, Juergen Gross wrote: >> For migration t

Re: [Xen-devel] [PATCH] libxc: try to find last used pfn when migrating

2015-11-30 Thread Andrew Cooper
On 30/11/15 08:17, Juergen Gross wrote: > On 27/11/15 18:16, Andrew Cooper wrote: >> On 27/11/15 15:53, Juergen Gross wrote: >>> On 27/11/15 16:33, Wei Liu wrote: On Fri, Nov 27, 2015 at 03:50:53PM +0100, Juergen Gross wrote: > For migration the last used pfn of a guest is needed to size t

Re: [Xen-devel] [PATCH] libxc: try to find last used pfn when migrating

2015-11-30 Thread Juergen Gross
On 27/11/15 18:16, Andrew Cooper wrote: > On 27/11/15 15:53, Juergen Gross wrote: >> On 27/11/15 16:33, Wei Liu wrote: >>> On Fri, Nov 27, 2015 at 03:50:53PM +0100, Juergen Gross wrote: For migration the last used pfn of a guest is needed to size the logdirty bitmap and as an upper bound

Re: [Xen-devel] [PATCH] libxc: try to find last used pfn when migrating

2015-11-27 Thread Andrew Cooper
On 27/11/15 15:53, Juergen Gross wrote: > On 27/11/15 16:33, Wei Liu wrote: >> On Fri, Nov 27, 2015 at 03:50:53PM +0100, Juergen Gross wrote: >>> For migration the last used pfn of a guest is needed to size the >>> logdirty bitmap and as an upper bound of the page loop. Unfortunately >>> there are

Re: [Xen-devel] [PATCH] libxc: try to find last used pfn when migrating

2015-11-27 Thread Juergen Gross
On 27/11/15 17:42, Andrew Cooper wrote: > On 27/11/15 14:50, Juergen Gross wrote: >> For migration the last used pfn of a guest is needed to size the >> logdirty bitmap and as an upper bound of the page loop. Unfortunately >> there are pv-kernels advertising a much higher maximum pfn as they >> are

Re: [Xen-devel] [PATCH] libxc: try to find last used pfn when migrating

2015-11-27 Thread Andrew Cooper
On 27/11/15 14:50, Juergen Gross wrote: > For migration the last used pfn of a guest is needed to size the > logdirty bitmap and as an upper bound of the page loop. Unfortunately > there are pv-kernels advertising a much higher maximum pfn as they > are really using in order to support memory hotpl

Re: [Xen-devel] [PATCH] libxc: try to find last used pfn when migrating

2015-11-27 Thread Juergen Gross
On 27/11/15 16:33, Wei Liu wrote: > On Fri, Nov 27, 2015 at 03:50:53PM +0100, Juergen Gross wrote: >> For migration the last used pfn of a guest is needed to size the >> logdirty bitmap and as an upper bound of the page loop. Unfortunately >> there are pv-kernels advertising a much higher maximum p

Re: [Xen-devel] [PATCH] libxc: try to find last used pfn when migrating

2015-11-27 Thread Juergen Gross
On 27/11/15 16:22, Ian Jackson wrote: > Juergen Gross writes ("Re: [Xen-devel] [PATCH] libxc: try to find last used > pfn when migrating"): >> xl migrate will use much less resources for a domain with a 3.x kernel >> started with max_mem being much larger than mem.

Re: [Xen-devel] [PATCH] libxc: try to find last used pfn when migrating

2015-11-27 Thread Wei Liu
On Fri, Nov 27, 2015 at 03:50:53PM +0100, Juergen Gross wrote: > For migration the last used pfn of a guest is needed to size the > logdirty bitmap and as an upper bound of the page loop. Unfortunately > there are pv-kernels advertising a much higher maximum pfn as they > are really using in order

Re: [Xen-devel] [PATCH] libxc: try to find last used pfn when migrating

2015-11-27 Thread Ian Jackson
Juergen Gross writes ("Re: [Xen-devel] [PATCH] libxc: try to find last used pfn when migrating"): > xl migrate will use much less resources for a domain with a 3.x kernel > started with max_mem being much larger than mem. E.g. in case you start > a domain on a small stand-by sy

Re: [Xen-devel] [PATCH] libxc: try to find last used pfn when migrating

2015-11-27 Thread David Vrabel
On 27/11/15 15:11, Juergen Gross wrote: > On 27/11/15 16:01, David Vrabel wrote: >> On 27/11/15 14:50, Juergen Gross wrote: >>> For migration the last used pfn of a guest is needed to size the >>> logdirty bitmap and as an upper bound of the page loop. Unfortunately >>> there are pv-kernels adverti

Re: [Xen-devel] [PATCH] libxc: try to find last used pfn when migrating

2015-11-27 Thread Ian Campbell
On Fri, 2015-11-27 at 16:11 +0100, Juergen Gross wrote: > On 27/11/15 16:01, David Vrabel wrote: > > On 27/11/15 14:50, Juergen Gross wrote: > > > For migration the last used pfn of a guest is needed to size the > > > logdirty bitmap and as an upper bound of the page loop. Unfortunately > > > there

Re: [Xen-devel] [PATCH] libxc: try to find last used pfn when migrating

2015-11-27 Thread Juergen Gross
On 27/11/15 16:01, David Vrabel wrote: > On 27/11/15 14:50, Juergen Gross wrote: >> For migration the last used pfn of a guest is needed to size the >> logdirty bitmap and as an upper bound of the page loop. Unfortunately >> there are pv-kernels advertising a much higher maximum pfn as they >> are

Re: [Xen-devel] [PATCH] libxc: try to find last used pfn when migrating

2015-11-27 Thread David Vrabel
On 27/11/15 14:50, Juergen Gross wrote: > For migration the last used pfn of a guest is needed to size the > logdirty bitmap and as an upper bound of the page loop. Unfortunately > there are pv-kernels advertising a much higher maximum pfn as they > are really using in order to support memory hotpl

[Xen-devel] [PATCH] libxc: try to find last used pfn when migrating

2015-11-27 Thread Juergen Gross
For migration the last used pfn of a guest is needed to size the logdirty bitmap and as an upper bound of the page loop. Unfortunately there are pv-kernels advertising a much higher maximum pfn as they are really using in order to support memory hotplug. This will lead to allocation of much more me