+ delayacct-add-memory-reclaim-delay-in-get_page_from_freelist.patch added to mm-unstable branch

+ delayacct-add-memory-reclaim-delay-in-get_page_from_freelist.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: delayacct: add memory reclaim delay in get_page_from_freelist
has been added to the -mm mm-unstable branch.  Its filename is
     delayacct-add-memory-reclaim-delay-in-get_page_from_freelist.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/delayacct-add-memory-reclaim-delay-in-get_page_from_freelist.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: liwenyu <wenyuli@ex.bilibili.com>
Subject: delayacct: add memory reclaim delay in get_page_from_freelist
Date: Wed, 20 Sep 2023 17:38:49 +0800

The current memory reclaim delay statistics only count the direct memory
reclaim of the task in do_try_to_free_pages().  In systems with NUMA open,
some tasks occasionally experience slower response times, but the total
count of reclaim does not increase, using ftrace can show that
node_reclaim has occurred.

The memory reclaim occurring in get_page_from_freelist() is also due to
heavy memory load.  To get the impact of tasks in memory reclaim, this
patch adds the statistics of the memory reclaim delay statistics for
__node_reclaim().

Link: https://lkml.kernel.org/r/181C946095F0252B+7cc60eca-1abf-4502-aad3-ffd8ef89d910@ex.bilibili.com
Signed-off-by: Wen Yu Li <wenyuli@ex.bilibili.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: <wangyun@bilibili.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/vmscan.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/mm/vmscan.c~delayacct-add-memory-reclaim-delay-in-get_page_from_freelist
+++ a/mm/vmscan.c
@@ -7350,6 +7350,7 @@ static int __node_reclaim(struct pglist_
 
 	cond_resched();
 	psi_memstall_enter(&pflags);
+	delayacct_freepages_start();
 	fs_reclaim_acquire(sc.gfp_mask);
 	/*
 	 * We need to be able to allocate from the reserves for RECLAIM_UNMAP
@@ -7372,6 +7373,7 @@ static int __node_reclaim(struct pglist_
 	memalloc_noreclaim_restore(noreclaim_flag);
 	fs_reclaim_release(sc.gfp_mask);
 	psi_memstall_leave(&pflags);
+	delayacct_freepages_end();
 
 	trace_mm_vmscan_node_reclaim_end(sc.nr_reclaimed);
 
_

Patches currently in -mm which might be from wenyuli@ex.bilibili.com are

delayacct-add-memory-reclaim-delay-in-get_page_from_freelist.patch