The patch titled Subject: mm/page_alloc: remove the throttling logic from the page allocator has been added to the -mm tree. Its filename is mm-page_alloc-remove-the-throttling-logic-from-the-page-allocator.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/mm-page_alloc-remove-the-throttling-logic-from-the-page-allocator.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/mm-page_alloc-remove-the-throttling-logic-from-the-page-allocator.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx> Subject: mm/page_alloc: remove the throttling logic from the page allocator The page allocator stalls based on the number of pages that are waiting for writeback to start but this should now be redundant. shrink_inactive_list() will wake flusher threads if the LRU tail are unqueued dirty pages so the flusher should be active. If it fails to make progress due to pages under writeback not being completed quickly then it should stall on VMSCAN_THROTTLE_WRITEBACK. Link: https://lkml.kernel.org/r/20211022144651.19914-6-mgorman@xxxxxxxxxxxxxxxxxxx Signed-off-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx> Cc: Andreas Dilger <adilger.kernel@xxxxxxxxx> Cc: "Darrick J . Wong" <djwong@xxxxxxxxxx> Cc: Dave Chinner <david@xxxxxxxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Jonathan Corbet <corbet@xxxxxxx> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: NeilBrown <neilb@xxxxxxx> Cc: Rik van Riel <riel@xxxxxxxxxxx> Cc: "Theodore Ts'o" <tytso@xxxxxxx> Cc: Vlastimil Babka <vbabka@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/page_alloc.c | 21 +-------------------- 1 file changed, 1 insertion(+), 20 deletions(-) --- a/mm/page_alloc.c~mm-page_alloc-remove-the-throttling-logic-from-the-page-allocator +++ a/mm/page_alloc.c @@ -4791,30 +4791,11 @@ should_reclaim_retry(gfp_t gfp_mask, uns trace_reclaim_retry_zone(z, order, reclaimable, available, min_wmark, *no_progress_loops, wmark); if (wmark) { - /* - * If we didn't make any progress and have a lot of - * dirty + writeback pages then we should wait for - * an IO to complete to slow down the reclaim and - * prevent from pre mature OOM - */ - if (!did_some_progress) { - unsigned long write_pending; - - write_pending = zone_page_state_snapshot(zone, - NR_ZONE_WRITE_PENDING); - - if (2 * write_pending > reclaimable) { - congestion_wait(BLK_RW_ASYNC, HZ/10); - return true; - } - } - ret = true; - goto out; + break; } } -out: /* * Memory allocation/reclaim might be called from a WQ context and the * current implementation of the WQ concurrency control doesn't _ Patches currently in -mm which might be from mgorman@xxxxxxxxxxxxxxxxxxx are mm-vmscan-throttle-reclaim-until-some-writeback-completes-if-congested.patch mm-vmscan-throttle-reclaim-and-compaction-when-too-may-pages-are-isolated.patch mm-vmscan-throttle-reclaim-when-no-progress-is-being-made.patch mm-writeback-throttle-based-on-page-writeback-instead-of-congestion.patch mm-page_alloc-remove-the-throttling-logic-from-the-page-allocator.patch mm-vmscan-centralise-timeout-values-for-reclaim_throttle.patch mm-vmscan-increase-the-timeout-if-page-reclaim-is-not-making-progress.patch mm-vmscan-delay-waking-of-tasks-throttled-on-noprogress.patch