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=-0.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 02BF8C43603 for ; Tue, 17 Dec 2019 12:19:48 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id BB21721739 for ; Tue, 17 Dec 2019 12:19:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="nW1RqOqJ" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BB21721739 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 574A88E005B; Tue, 17 Dec 2019 07:19:47 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 524BB8E0040; Tue, 17 Dec 2019 07:19:47 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 461688E005B; Tue, 17 Dec 2019 07:19:47 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0180.hostedemail.com [216.40.44.180]) by kanga.kvack.org (Postfix) with ESMTP id 337428E0040 for ; Tue, 17 Dec 2019 07:19:47 -0500 (EST) Received: from smtpin23.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with SMTP id E59AC8249980 for ; Tue, 17 Dec 2019 12:19:46 +0000 (UTC) X-FDA: 76274539572.23.run89_1b02dad3df763 X-HE-Tag: run89_1b02dad3df763 X-Filterd-Recvd-Size: 3947 Received: from mail-il1-f193.google.com (mail-il1-f193.google.com [209.85.166.193]) by imf17.hostedemail.com (Postfix) with ESMTP for ; Tue, 17 Dec 2019 12:19:45 +0000 (UTC) Received: by mail-il1-f193.google.com with SMTP id c4so3773845ilo.7 for ; Tue, 17 Dec 2019 04:19:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=rhMulIHbA6yrCBtl34rzmfSnJIKkct6s3ATbb92kwkQ=; b=nW1RqOqJej7U+Gi30b8Ebxo6jxeuuzLDFF5t6AtAzKamch6VCwh6hAr1TRxq3d8NTk F77nfO0x/MSql4fCo94/LZolCBOdwa0K5XIq040kwNRhzXVpJ2StKHkl/TUB6TAJbmQp t9mpS/Smt1rzSiXtczb64PXcIJtuzWYAD4Rw7/uRDcViJ9jwqAMte4by94Zbk7tV7+yj +jplzDGi7e5pamfrJcJxBOef5GbzAqLQb9EvAcS28TkxdESxKMVKLN7sCWWfvspbUPrR qlcjdC44PQn0Y2feX3nHDNxyY9lezTVjdXtQTUP8eCh6uY3qotdUrIv+UTMMteVIoVbQ oQVQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=rhMulIHbA6yrCBtl34rzmfSnJIKkct6s3ATbb92kwkQ=; b=IGf576fzjSsWqWwa1ShhniejP9Re+BHQ2IZObepWLoGWU6T5vwCGNmdruEUhxyavQb qySXnwfqW0NCbojxXsf6B1sRWRd/cR/NPIfIImL+/4eyUE7zJEo7nzD8/dvG6WQ6r9vA CfRES57mHPEXQqMH+MlZjF+PBsIQ0uVUMAVdLlkLqJOOtgP9uF23ORoBq2ZQZY0dcBjJ Np39YiOMcQkwBqY+JjU3yar8Nzgk5sO9jiPmE6ranbf+Vvdg2RaiqAkMZySFLXqoSmOs wh+BC3U1f0MsDNheMGpX2X3yYL1F5eqFNEKf4lwl82aDosl/MGJObJjGO3VQyDJHEwnY mQsQ== X-Gm-Message-State: APjAAAWvmcTztIXR7BfClGoUlO6W1kz+dFBs30XeRdIibMIfA3/pdSWa NmhQSbRKCJVJXJJ2jVL5yRz5YXUDpzrFwrkNmQw= X-Google-Smtp-Source: APXvYqzd1b6Nq7mjJEU+0QW65IlPVvFtP8uLP80Myzpt1VyVBGVcCm2LFT+aFiqiyyB9OVpYguUejmyeugtAWLj+lZw= X-Received: by 2002:a92:84ce:: with SMTP id y75mr16532399ilk.93.1576585184869; Tue, 17 Dec 2019 04:19:44 -0800 (PST) MIME-Version: 1.0 References: <1576582159-5198-1-git-send-email-laoar.shao@gmail.com> <20191217115603.GA10016@dhcp22.suse.cz> In-Reply-To: <20191217115603.GA10016@dhcp22.suse.cz> From: Yafang Shao Date: Tue, 17 Dec 2019 20:19:08 +0800 Message-ID: Subject: Re: [PATCH 0/4] memcg, inode: protect page cache from freeing inode To: Michal Hocko Cc: Johannes Weiner , Vladimir Davydov , Andrew Morton , Al Viro , Linux MM , linux-fsdevel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" 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: On Tue, Dec 17, 2019 at 7:56 PM Michal Hocko wrote: > > On Tue 17-12-19 06:29:15, Yafang Shao wrote: > > On my server there're some running MEMCGs protected by memory.{min, low}, > > but I found the usage of these MEMCGs abruptly became very small, which > > were far less than the protect limit. It confused me and finally I > > found that was because of inode stealing. > > What do you mean by this exactly. Are those inodes reclaimed by the > regular memory reclaim or by other means? Because shrink_node does > exclude shrinking slab for protected memcgs. By the regular memory reclaim, kswapd, direct reclaimer or memcg reclaimer. IOW, the current->reclaim_state it set. Take an example for you. kswapd balance_pgdat shrink_node_memcgs switch (mem_cgroup_protected) <<<< memory.current= 1024M memory.min = 512M a file has 800M page caches case MEMCG_PROT_NONE: <<<< hard limit is not reached. beak; shrink_lruvec shrink_slab <<< it may free the inode and the free all its page caches (800M) Hope it could clarify. Thanks Yafang