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bh=Ve/Ocmsy8HuxP+6kQzWQhSszhJgvBNDX8jcaj0nMCc4=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ifNf0Ij9G0rdZ+eBepTpikC57OTdhoCg+3Pusbrg+dSA9yQXwPrto3i4ecV1bGtcd ajqaOLFVukYhSlWLHmzOHNPwhdBjw+jx6I/yDQnHKXPt4hiJaZ3HRSLa99o/8wXup0 VdwuDDS0ZBz/nsLBID9XO5xAAcP/ZSzJ0giNFI10+1IgMdHLhVBk6gEhGKB9dkWlc5 XX+6jSPQirXonGLOrtej8ej8oYlksxj2E8DOei3UMD/DG2quZcTjzD1AaHLMYiB0nW UWTdu9YJ7XLwB7phFNla16cFRGoHl415ZFQk4WZqsTFTelj2SrgAVR7z6Tou72m1mx uxiPvm1EfljPA== 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 v9 13/16] mm/mglru: Reduce LRU lock contention by shrinking folio batches in inc_min_seq Date: Sun, 15 Nov 2026 04:08:00 +0800 Message-Id: <20261114200803.23129-14-baohua@kernel.org> X-Mailer: git-send-email 2.39.3 (Apple Git-146) In-Reply-To: <20261114200803.23129-1-baohua@kernel.org> References: <20261114200803.23129-1-baohua@kernel.org> X-Archived-By: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 26C2DC0006 X-Stat-Signature: 997ci44hnnz5bdypt6p1yzc8kjo4knk9 X-Rspam-User: X-HE-Tag: 1794686961-502564 X-HE-Meta: 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 cjYVhoHo cs2r4EwrTASYGG3aXXol4HUC7if8jVTKDQSfQhyqGuRqSUOzNiV0OeYi2ybnR4cY5NsV4JZ7mC2nFJPWE0b6nnM2/vL3grh+F+Z9njep6AlqSKgdusl4XEmyBhHp7myfMAnh73GdVZX+vsOV/UGjBmdmF3ORd7+x7CzhLiCUsK/ebKI8XnP0rfzlCH3Ct/ppYGbg95eEhNoUZdbgOkxV9fIQG2F7QBaoaktd3g3VVBC7GK1YZf8mp3LLQVMKOw/51GXiIlP3j/XAGW4lifO2hlpY3vRjC0GyoJ2fqp6JIlXFheZ/Fwh/5gKuCLB4gVcHYFjMpII/2r1XjCUOQTnSARVCsJhL+SOQaqKNQZpZAU4KJtmk= 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 c9e22a5cbb51..6cb905162cba 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -3914,7 +3914,7 @@ 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]); -- 2.39.3 (Apple Git-146)