Re: [Xen-devel] [PATCH] x86/PoD: skip eager reclaim when possible

2016-05-12 Thread George Dunlap
On 12/05/16 16:08, Jan Beulich wrote: On 12.05.16 at 16:40, wrote: >> On 10/05/16 14:44, Jan Beulich wrote: >>> Reclaiming pages is pointless when the cache can already satisfy all >>> outstanding PoD entries, and doing reclaims in that case can be very >>> harmful to performance when that me

Re: [Xen-devel] [PATCH] x86/PoD: skip eager reclaim when possible

2016-05-12 Thread Jan Beulich
>>> On 12.05.16 at 16:40, wrote: > On 10/05/16 14:44, Jan Beulich wrote: >> Reclaiming pages is pointless when the cache can already satisfy all >> outstanding PoD entries, and doing reclaims in that case can be very >> harmful to performance when that memory gets used by the guest, but >> only to

Re: [Xen-devel] [PATCH] x86/PoD: skip eager reclaim when possible

2016-05-12 Thread George Dunlap
On 10/05/16 14:44, Jan Beulich wrote: > Reclaiming pages is pointless when the cache can already satisfy all > outstanding PoD entries, and doing reclaims in that case can be very > harmful to performance when that memory gets used by the guest, but > only to store zeroes there. > > Signed-off-by:

Re: [Xen-devel] [PATCH] x86/PoD: skip eager reclaim when possible

2016-05-10 Thread Jan Beulich
>>> On 10.05.16 at 15:50, wrote: > On 10/05/16 14:44, Jan Beulich wrote: >> Reclaiming pages is pointless when the cache can already satisfy all >> outstanding PoD entries, and doing reclaims in that case can be very >> harmful to performance when that memory gets used by the guest, but >> only to

Re: [Xen-devel] [PATCH] x86/PoD: skip eager reclaim when possible

2016-05-10 Thread Wei Liu
On Tue, May 10, 2016 at 07:49:01AM -0600, Jan Beulich wrote: > >>> On 10.05.16 at 15:44, wrote: > > Reclaiming pages is pointless when the cache can already satisfy all > > outstanding PoD entries, and doing reclaims in that case can be very > > harmful to performance when that memory gets used by

Re: [Xen-devel] [PATCH] x86/PoD: skip eager reclaim when possible

2016-05-10 Thread Andrew Cooper
On 10/05/16 14:44, Jan Beulich wrote: > Reclaiming pages is pointless when the cache can already satisfy all > outstanding PoD entries, and doing reclaims in that case can be very > harmful to performance when that memory gets used by the guest, but > only to store zeroes there. > > Signed-off-by:

Re: [Xen-devel] [PATCH] x86/PoD: skip eager reclaim when possible

2016-05-10 Thread Jan Beulich
>>> On 10.05.16 at 15:44, wrote: > Reclaiming pages is pointless when the cache can already satisfy all > outstanding PoD entries, and doing reclaims in that case can be very > harmful to performance when that memory gets used by the guest, but > only to store zeroes there. > > Signed-off-by: Jan

[Xen-devel] [PATCH] x86/PoD: skip eager reclaim when possible

2016-05-10 Thread Jan Beulich
Reclaiming pages is pointless when the cache can already satisfy all outstanding PoD entries, and doing reclaims in that case can be very harmful to performance when that memory gets used by the guest, but only to store zeroes there. Signed-off-by: Jan Beulich --- a/xen/arch/x86/mm/p2m-pod.c +++