Currently balloon drivers (Virtio,XEN, HyperV, VMWare, ...)
inflate and deflate the guest memory size but there is no
way to know how much the memory size is changed by them.
A common use of the ballooning is to emulate [1]
hot plug and hot unplug - due to the complexity of the later.
Hotplug has a notifier and one can also check the updated
memory size.
To improve this add InflatedTotal and InflatedFree
to /proc/meminfo and implement a balloon notifier.
Amount of inflated memory can be used:
- si_meminfo(..) users can improve calculations
- adjust cache/buffer sizes
- adjust object/connection limits
- as a hint for the oom a killer
- by user space software that monitors memory pressure
Patches for the other balloon drivers will be done next.
Alexander Atanasov (4):
Make place for common balloon code
Enable balloon drivers to report inflated memory
Display inflated memory to users
drivers: virtio: balloon - update inflated memory
Documentation/filesystems/proc.rst | 6 +++
MAINTAINERS | 4 +-
arch/powerpc/platforms/pseries/cmm.c | 2 +-
drivers/misc/vmw_balloon.c | 2 +-
drivers/virtio/virtio_balloon.c | 7 +++-
fs/proc/meminfo.c | 10 +++++
...{balloon_compaction.h => balloon_common.h} | 20 +++++++++-
mm/Makefile | 2 +-
mm/{balloon_compaction.c => balloon_common.c} | 38 ++++++++++++++++++-
mm/migrate.c | 2 +-
mm/vmscan.c | 2 +-
11 files changed, 84 insertions(+), 11 deletions(-)
rename include/linux/{balloon_compaction.h => balloon_common.h} (90%)
rename mm/{balloon_compaction.c => balloon_common.c} (89%)
Cc: Michael S. Tsirkin <mst@xxxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Wei Liu <wei.liu@xxxxxxxxxx>
Cc: Nadav Amit <namit@xxxxxxxxxx>
Cc: pv-drivers@xxxxxxxxxx
Cc: Jason Wang <jasowang@xxxxxxxxxx>
Cc: virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx
Cc: "K. Y. Srinivasan" <kys@xxxxxxxxxxxxx>
Cc: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
Cc: Stephen Hemminger <sthemmin@xxxxxxxxxxxxx>
Cc: Dexuan Cui <decui@xxxxxxxxxxxxx>
Cc: linux-hyperv@xxxxxxxxxxxxxxx
Cc: Juergen Gross <jgross@xxxxxxxx>
Cc: Stefano Stabellini <sstabellini@xxxxxxxxxx>
Cc: Oleksandr Tyshchenko <oleksandr_tyshchenko@xxxxxxxx>
Cc: xen-devel@xxxxxxxxxxxxxxxxxxxx
--
2.31.1
