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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8855DC197A0 for ; Fri, 17 Nov 2023 16:20:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346080AbjKQQUE (ORCPT ); Fri, 17 Nov 2023 11:20:04 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49928 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231634AbjKQQUD (ORCPT ); Fri, 17 Nov 2023 11:20:03 -0500 Received: from outbound-smtp19.blacknight.com (outbound-smtp19.blacknight.com [46.22.139.246]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 14A45A4 for ; Fri, 17 Nov 2023 08:20:00 -0800 (PST) Received: from mail.blacknight.com (pemlinmail05.blacknight.ie [81.17.254.26]) by outbound-smtp19.blacknight.com (Postfix) with ESMTPS id 96A741C464C for ; Fri, 17 Nov 2023 16:19:58 +0000 (GMT) Received: (qmail 21917 invoked from network); 17 Nov 2023 16:19:58 -0000 Received: from unknown (HELO mail.blacknight.com) (mgorman@techsingularity.net@[81.17.254.19]) by 81.17.254.26 with ESMTPA; 17 Nov 2023 16:19:58 -0000 Date: Fri, 17 Nov 2023 16:19:56 +0000 From: Mel Gorman To: Michal Hocko Cc: Charan Teja Kalla , akpm@linux-foundation.org, david@redhat.com, vbabka@suse.cz, hannes@cmpxchg.org, quic_pkondeti@quicinc.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH V2 2/3] mm: page_alloc: correct high atomic reserve calculations Message-ID: <20231117161956.d3yjdxhhm4rhl7h2@techsingularity.net> References: <905d99651423ee85aeb7a71982b95ee9bb05ee99.1699104759.git.quic_charante@quicinc.com> <20231116095901.72oqtjoiqzt3tfhj@techsingularity.net> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Nov 16, 2023 at 01:52:26PM +0100, Michal Hocko wrote: > On Thu 16-11-23 09:59:01, Mel Gorman wrote: > [...] > > This patch in isolation seems fine with the caveat that such a small > > system may find the atomic reserves to be borderline useless. > > Yes, exactly what I had in mind. Would it make sense to reserve the the > pageblock only if it really is less than 1% of available memory? I'd have no objection with the caveat that we need to watch out for new bugs related to high-order atomic failures. If ths risk is noted in the changelog and that it's a revert candidate then any bisection should trivially find it. -- Mel Gorman SUSE Labs