On 2026-01-22 11:57, Roger Pau Monné wrote:
On Thu, Jan 22, 2026 at 09:40:01AM -0500, Jason Andryuk wrote:
On 2026-01-21 12:49, Roger Pau Monné wrote:
I haven't tested it yet to see whether that's OK to do on PV, I would
think PV and PVH would be the same here, since the setting of the
xenstore target value is based in the return of
XENMEM_current_reservation for both.
On a system with 32GB and dom0=pvh dom0_mem=7G:
[ 0.295201] xen:balloon: current_pages: 1835007 get_num_physpages 8220126
xen_released_pages 6385120
[ 0.295201] ------------[ cut here ]------------
[ 0.295201] Released pages underflow current target
8220126 - 6385120 = 1835006
And also for PV:
[ 1.406923] xen:balloon: current_pages: 1835008 get_num_physpages 8220127
xen_released_pages 6385120
[ 1.406928] ------------[ cut here ]------------
[ 1.406931] Released pages underflow current target
So we don't want to subtract xen_released_pages for dom0. Is
xen_released_pages expected to be non-zero for a domU?
Oh, yes. In fact I think the patch here is wrong for PV dom0, as it
shouldn't subtract xen_released_pages from xen_start_info->nr_pages.
I will need to send v2.
To be clear, the numbers and warning are from the follow on
current_reservation patch.
Regards,
Jason
