mm/mglru: don't sync disk for each aging cycle

wakeup_flusher_threads() was added under the assumption that if a system
runs out of clean cold pages, it might want to write back dirty pages more
aggressively so that they can become clean and be dropped.

However, doing so can breach the rate limit a system wants to impose on
writeback, resulting in early SSD wearout.

Link: https://lkml.kernel.org/r/YzSiWq9UEER5LKup@google.com
Fixes: d6cb17c5af77 ("mm: multi-gen LRU: support page table walks")
Signed-off-by: Yu Zhao <yuzhao@google.com>
Reported-by: Axel Rasmussen <axelrasmussen@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/vmscan.c b/mm/vmscan.c
index c5a4bff11da695533f1e50ba561b5e5d472121d7..3240d5dd7784aa82feacdccad45f02abe03bf465 100644 (file)
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -4413,8 +4413,6 @@ done:
        if (wq_has_sleeper(&lruvec->mm_state.wait))
                wake_up_all(&lruvec->mm_state.wait);
 
-       wakeup_flusher_threads(WB_REASON_VMSCAN);
-
        return true;
 }