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| author | Yangming <yangming73@huawei.com> | 2023-03-09 07:52:57 +0000 |
|---|---|---|
| committer | Michael S. Tsirkin <mst@redhat.com> | 2023-04-21 04:25:52 -0400 |
| commit | e919402b9e05c964561623ddada9d49d0a05b850 (patch) | |
| tree | 44d9118eed1819c65cc55b238bf9392c90f3d2ee /hw/mem | |
| parent | f21e95ee97d5adb4a274b48c6c8f70a221c1f513 (diff) | |
| download | qemu-e919402b9e05c964561623ddada9d49d0a05b850.zip qemu-e919402b9e05c964561623ddada9d49d0a05b850.tar.gz qemu-e919402b9e05c964561623ddada9d49d0a05b850.tar.bz2 | |
virtio-balloon: optimize the virtio-balloon on the ARM platform
Optimize the virtio-balloon feature on the ARM platform by adding
a variable to keep track of the current hot-plugged pc-dimm size,
instead of traversing the virtual machine's memory modules to count
the current RAM size during the balloon inflation or deflation
process. This variable can be updated only when plugging or unplugging
the device, which will result in an increase of approximately 60%
efficiency of balloon process on the ARM platform.
We tested the total amount of time required for the balloon inflation process on ARM:
inflate the balloon to 64GB of a 128GB guest under stress.
Before: 102 seconds
After: 42 seconds
Signed-off-by: Qi Xi <xiqi2@huawei.com>
Signed-off-by: Ming Yang yangming73@huawei.com
Message-Id: <e13bc78f96774bfab4576814c293aa52@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Diffstat (limited to 'hw/mem')
| -rw-r--r-- | hw/mem/pc-dimm.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/hw/mem/pc-dimm.c b/hw/mem/pc-dimm.c index 50ef832..37f1f4c 100644 --- a/hw/mem/pc-dimm.c +++ b/hw/mem/pc-dimm.c @@ -81,6 +81,10 @@ void pc_dimm_plug(PCDIMMDevice *dimm, MachineState *machine) memory_device_plug(MEMORY_DEVICE(dimm), machine); vmstate_register_ram(vmstate_mr, DEVICE(dimm)); + /* count only "real" DIMMs, not NVDIMMs */ + if (!object_dynamic_cast(OBJECT(dimm), TYPE_NVDIMM)) { + machine->device_memory->dimm_size += memory_region_size(vmstate_mr); + } } void pc_dimm_unplug(PCDIMMDevice *dimm, MachineState *machine) @@ -90,6 +94,9 @@ void pc_dimm_unplug(PCDIMMDevice *dimm, MachineState *machine) memory_device_unplug(MEMORY_DEVICE(dimm), machine); vmstate_unregister_ram(vmstate_mr, DEVICE(dimm)); + if (!object_dynamic_cast(OBJECT(dimm), TYPE_NVDIMM)) { + machine->device_memory->dimm_size -= memory_region_size(vmstate_mr); + } } static int pc_dimm_slot2bitmap(Object *obj, void *opaque) |