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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 2B572C433E6 for ; Thu, 18 Feb 2021 10:55:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D7A2864E85 for ; Thu, 18 Feb 2021 10:55:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231279AbhBRKur (ORCPT ); Thu, 18 Feb 2021 05:50:47 -0500 Received: from mx2.suse.de ([195.135.220.15]:47104 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230438AbhBRJgT (ORCPT ); Thu, 18 Feb 2021 04:36:19 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1613640929; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=xOTaO1omfPlkRnn1YUpa+vtFf0rS0L1QNZvI+45woCc=; b=HIcMHhdtvXFMw+pM36OAmXseZ8sHd0dr5U1/g2L7/DfZCLYBV2fKm6FBqY+B3C7OyTBr4b JK1fxUh1wClPo3hyzoD16YOjj3NE+IzkczYh/KuICS1j5MvlxstZsNtVSOVR3L3maGK+tM a8MeMgYo2lpSw84OSmqvcIsLTvdX9XA= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 80283ACD9; Thu, 18 Feb 2021 09:35:29 +0000 (UTC) Date: Thu, 18 Feb 2021 10:35:22 +0100 From: Michal Hocko To: David Hildenbrand Cc: Minchan Kim , Andrew Morton , linux-mm , LKML , joaodias@google.com Subject: Re: [PATCH] mm: be more verbose for alloc_contig_range faliures Message-ID: References: <20210217163603.429062-1-minchan@kernel.org> <2f167b3c-5f0a-444a-c627-49181fc8fe0d@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <2f167b3c-5f0a-444a-c627-49181fc8fe0d@redhat.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu 18-02-21 10:02:43, David Hildenbrand wrote: > On 18.02.21 09:56, Michal Hocko wrote: > > On Wed 17-02-21 08:36:03, Minchan Kim wrote: > > > alloc_contig_range is usually used on cma area or movable zone. > > > It's critical if the page migration fails on those areas so > > > dump more debugging message like memory_hotplug unless user > > > specifiy __GFP_NOWARN. > > > > I agree with David that this has a potential to generate a lot of output > > and it is not really clear whether it is worth it. Page isolation code > > already has REPORT_FAILURE mode which currently used only for the memory > > hotplug because this was just too noisy from the CMA path - d381c54760dc > > ("mm: only report isolation failures when offlining memory"). > > > > Maybe migration failures are less likely to fail but still. > > Side note: I really dislike that uncontrolled error reporting on memory > offlining path we have enabled as default. Yeah, it might be useful for > ZONE_MOVABLE in some cases, but otherwise it's just noise. > > Just do a "sudo stress-ng --memhotplug 1" and see the log getting flooded Anyway we can discuss this in a separate thread but I think this is not a representative workload. -- Michal Hocko SUSE Labs