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=-8.6 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_PASS,USER_IN_DEF_DKIM_WL autolearn=ham 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 38BA5C04EB9 for ; Wed, 5 Dec 2018 19:00:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E765720989 for ; Wed, 5 Dec 2018 19:00:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="g+ECFszL" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E765720989 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728041AbeLETAW (ORCPT ); Wed, 5 Dec 2018 14:00:22 -0500 Received: from mail-pg1-f193.google.com ([209.85.215.193]:42175 "EHLO mail-pg1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727436AbeLETAW (ORCPT ); Wed, 5 Dec 2018 14:00:22 -0500 Received: by mail-pg1-f193.google.com with SMTP id d72so9429860pga.9 for ; Wed, 05 Dec 2018 11:00:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:in-reply-to:message-id:references :user-agent:mime-version; bh=wsnQOTkUnx8CL9Z5KKvss9h3kVd/jnVBhTMb767fQbw=; b=g+ECFszLYuOCu8VNcBp+VwxRMqjonff3N+NbRSSMk3wjlEoR5TBOPQFBGc36r2aijQ /Bn6bmCly/YFqDNvTjVwbnworLIyAQHECYHW4EmbRXB3i54Atrs1abfMaUTDfrSw41mS gY2lcExOQlPfzlXcVoEhmqdIj5Ea/7YQKZ4EP/m4RRAppkUwdYU2eg41cRZa1awnGBTD 71y58jGSikbss7rggBoGJsyxt6RYVXqBVmdU4QpFPWBtrj4Wg3l+zgjpRzj7VgiQ/kyF OIKVDnlPT4nVKEut6UKsAUBOeOFhqHWn555guhYMpH8MokD8Kwidagti6CXLyNzdg9va 1FFw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:in-reply-to:message-id :references:user-agent:mime-version; bh=wsnQOTkUnx8CL9Z5KKvss9h3kVd/jnVBhTMb767fQbw=; b=WoSjJpsHqg7pJv5nxvSRfZAnT8hTBFlkAh1/v/sHHWoIXQDrfUp7+IZ3Yd9Q+x5QnL 7Ua+hlpDNmINvYo3K8YIhNP9ib0rFzJ05gHyo7ps31JfGwF04Xl5bSVlNtsrNxciP2XK kR1Lz0WVZijnz7CooNzJswPdyJlRzovDBDv7PO2dMeq7xCDr2BGoinL2nYYX3E/cbV/t UolraAfDCYdjX1Ju59lIyv5z6/5V1gvUHCQwE1g2CyEJpSaZFGDiXTLuYyvOwYmD1erC a26m1+Bwy/6/UTDKuM2zH2wkHLEXJVmKPJ3XqrHEDQAnzlUgelFM2jx8ZWKhtaxLLWtA YtiA== X-Gm-Message-State: AA+aEWYoV7Er67zl1enITtiiIWKOttg3ZvX+bXLytwcmgl3FYValPTdt 3DuZVILmf/jcPTRQTNk1w/lBGQ== X-Google-Smtp-Source: AFSGD/V1hBd4x0dcDx572+XW/Nkd2IBflIu1wpoVt7yFaKZjgb4pinad0KYlG6co7XVnUlzG/aF3bQ== X-Received: by 2002:a62:ca9c:: with SMTP id y28mr25359270pfk.236.1544036421224; Wed, 05 Dec 2018 11:00:21 -0800 (PST) Received: from [2620:15c:17:3:3a5:23a7:5e32:4598] ([2620:15c:17:3:3a5:23a7:5e32:4598]) by smtp.gmail.com with ESMTPSA id g28sm38393114pfd.100.2018.12.05.11.00.20 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 05 Dec 2018 11:00:20 -0800 (PST) Date: Wed, 5 Dec 2018 11:00:19 -0800 (PST) From: David Rientjes X-X-Sender: rientjes@chino.kir.corp.google.com To: Pingfan Liu cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrew Morton , Michal Hocko , Vlastimil Babka , Mike Rapoport , Bjorn Helgaas , Jonathan Cameron Subject: Re: [PATCH] mm/alloc: fallback to first node if the wanted node offline In-Reply-To: Message-ID: References: <1543892757-4323-1-git-send-email-kernelfans@gmail.com> User-Agent: Alpine 2.21 (DEB 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 5 Dec 2018, Pingfan Liu wrote: > > > And rather than using first_online_node, would next_online_node() work? > > > > > What is the gain? Is it for memory pressure on node0? > > > Maybe I got your point now. Do you try to give a cheap assumption on > nearest neigh of this node? > It's likely better than first_online_node, but probably going to be the same based on the node ids that you have reported since the nodemask will simply wrap around back to the first node.