From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id ED013C04AB6 for ; Tue, 28 May 2019 06:44:45 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id A252E208C3 for ; Tue, 28 May 2019 06:44:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A252E208C3 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 3C7476B0270; Tue, 28 May 2019 02:44:45 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 377E06B0276; Tue, 28 May 2019 02:44:45 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 219066B0278; Tue, 28 May 2019 02:44:45 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from mail-pl1-f200.google.com (mail-pl1-f200.google.com [209.85.214.200]) by kanga.kvack.org (Postfix) with ESMTP id DED196B0270 for ; Tue, 28 May 2019 02:44:44 -0400 (EDT) Received: by mail-pl1-f200.google.com with SMTP id 91so618424pla.7 for ; Mon, 27 May 2019 23:44:44 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-original-authentication-results:x-gm-message-state:from:to:cc :subject:date:message-id; bh=fTV9+QJ3Qlr+eWA8hqTAepwEMa3PO/pXGof/Ta/9BdY=; b=t9aYiQBDdhGvCuyn3n/fOxb8XYKtWvbDiCqKiAAH4Olp7bo5h1ycdiNWlYEGAazk70 biAjPMtGQikknI+Fs0b8sxqYjGw6uGBq5zKEUK8uGS3G6W3N82fa5yeaAc4r8qbvUCQw 8qb0dKtDIMHOQhoaMtBcwbHIKD8mwXxboxn7FqyYuzIh/+pyCYfw/CeiCdd79qxgV6rR 6YAyoWCX9p9ifQasGugr6X2WLqo6Wujq35QKMdkTReJOtQ2Yj/Oau2eExOHyBKlO6aAG JyQwY5Bv/k6kIBT3pDTdVYlGwhWtGesZI26jS2o4PNTly3xONJsRwZK+S6KsWdiwTfN3 +BdA== X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of yang.shi@linux.alibaba.com designates 47.88.44.37 as permitted sender) smtp.mailfrom=yang.shi@linux.alibaba.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=alibaba.com X-Gm-Message-State: APjAAAV2Mun/qzUV7pYDrgwGEJY8yslUgHKTlE7Hx3pcl5QJEBW/f4IA Jw1dZk2cjkDYaBveq34EHdAJaK/MBttoQjH6Bru5/JhAZXN1f6JgOwJmVsQuAPzO2bovjKn0ghf 2tSrd58xgyvP3hzqjxG6at96qHMI5Z1NfYv7/ghmCH5g8BtkG91foC7jKygloeHKdPw== X-Received: by 2002:a62:2b94:: with SMTP id r142mr50818620pfr.184.1559025884549; Mon, 27 May 2019 23:44:44 -0700 (PDT) X-Google-Smtp-Source: APXvYqxnieoFpuNpWC+jB5HXx/L5rr8yPHfKsjbRUeI/PqbIZkQQhq1dla9O4Euv9VO8ISKj39Dc X-Received: by 2002:a62:2b94:: with SMTP id r142mr50818528pfr.184.1559025883224; Mon, 27 May 2019 23:44:43 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1559025883; cv=none; d=google.com; s=arc-20160816; b=emfC/Rmzod0JVyXGfR8lb+dtKO89GL8Wkpzv5Ozd7WM91x59CLlitCM4uEIHVbJoXd WJkOVRfq7YKnD2f1cvKFf4XA7dTHeJpD2JSGWR0ejpcJBsYGeedBhnlPwxwCSTm/7Qyt RUjKUeoqGmyuuPI7TJ7t2CZ7gYqVvqSbVuKYxI7UbCTQmSRnv22KpBp3rKpixg5FBzMf 85KjtCi49DcTaI7FcXZZiG3lbAhSJtbMKi/8+1C8PuN6thMiXceg0dUA3MZALXKOpWcr Y9cfPNgupiFSi+QjO6zNBzxDRV3QY4NlUu+pVvkFsESvhFHizW1xyXC3iRlml85KU5X+ zksg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=message-id:date:subject:cc:to:from; bh=fTV9+QJ3Qlr+eWA8hqTAepwEMa3PO/pXGof/Ta/9BdY=; b=hwKRMi8yOY2AenKn/mdBC1EXDtOUCihFXr7Q6X4/wUzgC9rAuUYPsvif82EHtePLNy OImebKOY8ENSnMTNpkyJsU/UYiS0jycwCrQT24CtINNqHYVr+i/DZYAVzf+VjD3Ryw1w L3+ucBJ6dgqXqRMZfWpM99P7m5yugw/u0gNAhdokA+WhhNzhKZtVjfjA3S8xbdZovS4k tOUxTEullk5TcW0csDVdN1HIVZn3Tm/WdrUQHCRZwyXzX3xgcXihFhhlyipuFK9mOynb fyQiYjwIYCZwpeHzky8ZKdS4RrGYY9bFicf0KOJ398Pc4GArgKWjCty+q6gR8yBtUUXW 97pQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of yang.shi@linux.alibaba.com designates 47.88.44.37 as permitted sender) smtp.mailfrom=yang.shi@linux.alibaba.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=alibaba.com Received: from out4437.biz.mail.alibaba.com (out4437.biz.mail.alibaba.com. [47.88.44.37]) by mx.google.com with ESMTPS id n129si23508102pfn.106.2019.05.27.23.44.41 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 27 May 2019 23:44:43 -0700 (PDT) Received-SPF: pass (google.com: domain of yang.shi@linux.alibaba.com designates 47.88.44.37 as permitted sender) client-ip=47.88.44.37; Authentication-Results: mx.google.com; spf=pass (google.com: domain of yang.shi@linux.alibaba.com designates 47.88.44.37 as permitted sender) smtp.mailfrom=yang.shi@linux.alibaba.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=alibaba.com X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R841e4;CH=green;DM=||false|;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04420;MF=yang.shi@linux.alibaba.com;NM=1;PH=DS;RN=13;SR=0;TI=SMTPD_---0TSrpwyt_1559025859; Received: from e19h19392.et15sqa.tbsite.net(mailfrom:yang.shi@linux.alibaba.com fp:SMTPD_---0TSrpwyt_1559025859) by smtp.aliyun-inc.com(127.0.0.1); Tue, 28 May 2019 14:44:28 +0800 From: Yang Shi To: ying.huang@intel.com, hannes@cmpxchg.org, mhocko@suse.com, mgorman@techsingularity.net, kirill.shutemov@linux.intel.com, josef@toxicpanda.com, hughd@google.com, shakeelb@google.com, hdanton@sina.com, akpm@linux-foundation.org Cc: yang.shi@linux.alibaba.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [v7 PATCH 1/2] mm: vmscan: remove double slab pressure by inc'ing sc->nr_scanned Date: Tue, 28 May 2019 14:44:18 +0800 Message-Id: <1559025859-72759-1-git-send-email-yang.shi@linux.alibaba.com> X-Mailer: git-send-email 1.8.3.1 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: The commit 9092c71bb724 ("mm: use sc->priority for slab shrink targets") has broken up the relationship between sc->nr_scanned and slab pressure. The sc->nr_scanned can't double slab pressure anymore. So, it sounds no sense to still keep sc->nr_scanned inc'ed. Actually, it would prevent from adding pressure on slab shrink since excessive sc->nr_scanned would prevent from scan->priority raise. The bonnie test doesn't show this would change the behavior of slab shrinkers. w/ w/o /sec %CP /sec %CP Sequential delete: 3960.6 94.6 3997.6 96.2 Random delete: 2518 63.8 2561.6 64.6 The slight increase of "/sec" without the patch would be caused by the slight increase of CPU usage. Cc: Josef Bacik Cc: Michal Hocko Acked-by: Johannes Weiner Signed-off-by: Yang Shi --- v4: Added Johannes's ack mm/vmscan.c | 5 ----- 1 file changed, 5 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 7acd0af..b65bc50 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1137,11 +1137,6 @@ static unsigned long shrink_page_list(struct list_head *page_list, if (!sc->may_unmap && page_mapped(page)) goto keep_locked; - /* Double the slab pressure for mapped and swapcache pages */ - if ((page_mapped(page) || PageSwapCache(page)) && - !(PageAnon(page) && !PageSwapBacked(page))) - sc->nr_scanned++; - may_enter_fs = (sc->gfp_mask & __GFP_FS) || (PageSwapCache(page) && (sc->gfp_mask & __GFP_IO)); -- 1.8.3.1