On 5/25/21 10:01 AM, Mel Gorman wrote: > The PCP high watermark is based on the number of online CPUs so the > watermarks must be adjusted during CPU hotplug. At the time of > hot-remove, the number of online CPUs is already adjusted but during > hot-add, a delta needs to be applied to update PCP to the correct > value. After this patch is applied, the high watermarks are adjusted > correctly. > > # grep high: /proc/zoneinfo | tail -1 > high: 649 > # echo 0 > /sys/devices/system/cpu/cpu4/online > # grep high: /proc/zoneinfo | tail -1 > high: 664 > # echo 1 > /sys/devices/system/cpu/cpu4/online > # grep high: /proc/zoneinfo | tail -1 > high: 649 > > Signed-off-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx> Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
