Proactive compaction for the kernel

When the current node's kswapd thread is active (to avoid interfering with the reclaim process).
When there is contention on the per-node lru_lock or per-zone lock (to avoid hurting non-background, latency-sensitive contexts).
When there is no progress (reduction in node's fragmentation score value) after a round of compaction.

hello, for your described backoff mechanism, can you share your achievement from patch.