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bh=vpSsC6eHA17zXSkm9xogF1qAqxxkKO+eDjMPRSKEUa8=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=W1olGJcWb+1DuQiRIqlvQtmiFzXY8mMkYsK+/jgjpcG8q6M+7TH8tH6eOsb8r5reg rZY80I2i3xENqep5AjQtcGiUB8SkMAR6xTvZRI1clyWM8QnkXCKe2v1AUuWLdWhrCK hUhymLkVLquKL1tTW11hEim8Rgeh/AmAxSzMjGMv+2IjO9Lx6AVXMljKCxqr8Qh97D ujXZsfzWsQ8oD8270gCI5aWFfXLKMy8OSsr5cPUv41l5eN50RKaLNK4oWlOPMnVTpa yixl7sdn5p50BC/bgEnyp0OMwD2v/fNk2B2YSX38yfcAAIJ1uugSnCdPfgpE//uvOO nk8QH7W6wyEZQ== From: "Barry Song (Xiaomi)" To: akpm@linux-foundation.org, linux-mm@kvack.org Cc: axelrasmussen@google.com, baolin.wang@linux.alibaba.com, baoquan.he@linux.dev, hannes@cmpxchg.org, hui.zhu@linux.dev, kasong@tencent.com, kunwu.chan@gmail.com, liam@infradead.org, lianux.mm@gmail.com, linux-kernel@vger.kernel.org, liuxiang.277@bytedance.com, lyugaofei@xiaomi.com, mhocko@kernel.org, mhocko@suse.com, qi.zheng@linux.dev, ridong.chen@linux.dev, rppt@kernel.org, ryncsn@gmail.com, shakeel.butt@linux.dev, surenb@google.com, wangzicheng@honor.com, weixugc@google.com, yuanchu@google.com, zhangbo56@xiaomi.com, zhuhui@kylinos.cn, sidchintamaneni@gmail.com, "Barry Song (Xiaomi)" Subject: [PATCH v6 12/15] mm/mglru: Reduce LRU lock contention by shrinking folio batches in inc_min_seq Date: Wed, 11 Nov 2026 04:20:22 +0800 Message-Id: <20261110202025.25736-13-baohua@kernel.org> X-Mailer: git-send-email 2.39.3 (Apple Git-146) In-Reply-To: <20261110202025.25736-1-baohua@kernel.org> References: <20261110202025.25736-1-baohua@kernel.org> X-Archived-By: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Stat-Signature: 6uobpj7dw34k67r7ihdeasjydg35h3ad X-Rspamd-Queue-Id: E43761C000D X-Rspam-User: X-Rspamd-Server: rspam11 X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_PASS, SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=4.0.1 X-HE-Tag: 1794342097-135925 X-HE-Meta: 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 4Cm26yxG itwM4zkY/S1/krjC4y+rJJgJOl+FELIwALFbCqeBH+AC2CEF0tQjmSlF4sdYJTR9bThV9Zd22ejXI7AQEplCsE5w/UA6ytkmUAIVQ3F0wUkQ923pXZqSIAK4r6kRJm5h35cBFDldbH84Kv+byq2hkvdlqekbzitjPiq7xzx7IonGI43tUmm8A7xY95FZxznPDmbyS8xwEjMWeIhlLRwCUOIHcwrqXMXyCtcUVj03MUj93qhJLYhbzPwPNeoDqAEeq9qxtFbUnbUaK9qKpFqXoI1ucoPZEge0Wl6r6Thk/5nG8KKcd1s+R4ZbpT5roatxDEl8foLoKhsfzv2zT6K6I3tv5pUxTd/4vuMHP Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 Reduce the number of folios moved from the oldest generation to the second-oldest generation in each batch. This shortens the time the lruvec lock is held, allowing concurrent LRU operations to make progress and significantly reducing LRU lock contention. Signed-off-by: Barry Song (Xiaomi) --- mm/vmscan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index bfc9789a999a..34faabe617ae 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -3911,7 +3911,7 @@ static inline void flush_lru_batch(struct list_head *head, struct list_head **ba static bool inc_min_seq(struct lruvec *lruvec, int type, int swappiness) { int zone; - int remaining = MAX_LRU_BATCH; + int remaining = MIN_LRU_BATCH; struct lru_gen_folio *lrugen = &lruvec->lrugen; int hist = lru_hist_from_seq(lrugen->min_seq[type]); int new_gen, old_gen = lru_gen_from_seq(lrugen->min_seq[type]); -- 2.34.1