ascend inclusion
category: perf
bugzilla: https://gitee.com/openeuler/kernel/issues/I4EUVI
CVE: NA

-------------------------------------------------

We did an compaction experiment on Hi1951. First creating external
fragmentation, then echo 1 > /proc/sys/vm/compact_memory.

Fragmentation size | 0G   | 2G   | 4G  | 8G
Compaction time(s) | 0.07 | 0.85 | 1.7 | 3.4

Obviously, sysctl_compaction_handler has a big performance impact.

We optimize share pool compact procedure as follows:
1. At most one compact daemon is allowed.
2. Creating a compact daemon is only allowed when the last one is
finished at least *sysctl_sp_compact_interval* seconds ago.
Signed-off-by: NTang Yizhou <tangyizhou@huawei.com>
Reviewed-by: NDing Tianhong <dingtianhong@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
Reviewed-by: NWeilong Chen <chenweilong@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>