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=-3.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 1EDA9C4363D for ; Wed, 23 Sep 2020 02:35:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D4CAD20725 for ; Wed, 23 Sep 2020 02:35:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=bytedance-com.20150623.gappssmtp.com header.i=@bytedance-com.20150623.gappssmtp.com header.b="gpENJad7" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727248AbgIWCfn (ORCPT ); Tue, 22 Sep 2020 22:35:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36468 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727217AbgIWCfm (ORCPT ); Tue, 22 Sep 2020 22:35:42 -0400 Received: from mail-lf1-x142.google.com (mail-lf1-x142.google.com [IPv6:2a00:1450:4864:20::142]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0A2E3C0613D2 for ; Tue, 22 Sep 2020 19:35:42 -0700 (PDT) Received: by mail-lf1-x142.google.com with SMTP id q8so20290878lfb.6 for ; Tue, 22 Sep 2020 19:35:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=HNLILPO9KGBr2EiE7fPnteeqqVFqeTm0/utbd5V0UfM=; b=gpENJad7aIY/S5kBL5o8YVttNP6P373hhEXKz6ErBwsU/D+zf22imm1nkW4ERBaSHD zpAbAVk6UoSZYDLYJDZkFGLPhDVWGMO30j0pUcW7h49Tryqf3NzJu4RZcL1iD02GoqA6 MG4REMrV1LplGXzEGHcMfLHjAQZ1DpNK4aAMFIQctSZ6kzBGbm0dg2ZTVSIvvckdxqRX A8p1DU39WBmIgc/L4nnjM4X9tMLRq8LvlGdaeOQbqxSz6Ff+SemO4COh6UTnhUpLf6VS txktKu+z0qVosUhE2kp0VE8x0/fTRFl8/cXeYa/Z0ziyNv7xI9D9QFTcZQvRCBscssRC /Uug== 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=HNLILPO9KGBr2EiE7fPnteeqqVFqeTm0/utbd5V0UfM=; b=DnPEdMHD+ECdfMzr68uq5trKTLn8ZyCt+2nSKC/YzfEazqczDWXmcs1qUzcYFo9m2Q 6/XSb0kl6mSiJxIQrNwTVqyhNGUD1yvQoWHmY5rw+ngGfGQW+2OIjXQtps9TSDJDz4vR MLr8JZCPhXzdAzYCFDrwgSyKGCp5kfIPiDN+uGjkKwv0gJ3FwEx2OH6N0d1tiSv4ZqZ9 G3TSbj/X8c1nhSQBJXCCLQ4dQ8mPv7rFkEzordiHksLo1UWkbwjZmt9wHI7nVgSv0w1M GaxX71rAkIJ91/kC/NdukM5XS8fd0TTr8G5UiXyETmdxtsT0mwMfpI16EWE2ENqAyls0 8w5g== X-Gm-Message-State: AOAM531BUnKvTskOPfH6I0JtbhUK60y2sfscXyC0LBZ7ixdHHA2bFywS XFtAcRWG0/iUQ1oW0tHqoD8aCw8lAGgAqrKs82r7fw== X-Google-Smtp-Source: ABdhPJxyzcM22PrIegi03Dy1GMhdk2CcQ8TxOfp4CD5IlwC/YoSTAHHbEzvDZ3zvZGe7TGoUuOqs4yQ/LKXQgaUQgH8= X-Received: by 2002:a19:8789:: with SMTP id j131mr2439699lfd.90.1600828540307; Tue, 22 Sep 2020 19:35:40 -0700 (PDT) MIME-Version: 1.0 References: <20200921080255.15505-1-zangchunxin@bytedance.com> <20200921081200.GE12990@dhcp22.suse.cz> <20200921110505.GH12990@dhcp22.suse.cz> <20200922095136.GA9682@chrisdown.name> <20200922104252.GB9682@chrisdown.name> <20200922124344.GA34296@chrisdown.name> In-Reply-To: <20200922124344.GA34296@chrisdown.name> From: Chunxin Zang Date: Wed, 23 Sep 2020 10:35:29 +0800 Message-ID: Subject: Re: [External] Re: [PATCH] mm/memcontrol: Add the drop_cache interface for cgroup v2 To: Chris Down Cc: Michal Hocko , Yafang Shao , Johannes Weiner , Vladimir Davydov , Andrew Morton , Tejun Heo , lizefan@huawei.com, Jonathan Corbet , Alexei Starovoitov , Daniel Borkmann , kafai@fb.com, Song Liu , Yonghong Song , andriin@fb.com, john.fastabend@gmail.com, kpsingh@chromium.org, Cgroups , linux-doc@vger.kernel.org, Linux MM , LKML , netdev , bpf@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Tue, Sep 22, 2020 at 8:43 PM Chris Down wrote: > > Chunxin Zang writes: > >Please forgive me for not being able to understand why setting > >memory.low for Type_A can solve the problem. > >In my scene, Type_A is the most important, so I will set 100G to memory.low. > >But 'memory.low' only takes effect passively when the kernel is > >reclaiming memory. It means that reclaim Type_B's memory only when > >Type_A in alloc memory slow path. This will affect Type_A's > >performance. > >We want to reclaim Type_B's memory in advance when A is expected to be busy. > > That's what kswapd reclaim is for, so this distinction is meaningless without > measurements :-) Thanks for these suggestions, I will give it a try. Best wishes Chunxin