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=-2.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 0B634C433ED for ; Thu, 1 Apr 2021 20:12:43 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 855F9610CF for ; Thu, 1 Apr 2021 20:12:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 855F9610CF 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 1E5B86B00B3; Thu, 1 Apr 2021 16:12:42 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 1965E6B00B5; Thu, 1 Apr 2021 16:12:42 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0378D6B00B6; Thu, 1 Apr 2021 16:12:41 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0143.hostedemail.com [216.40.44.143]) by kanga.kvack.org (Postfix) with ESMTP id D5FB66B00B3 for ; Thu, 1 Apr 2021 16:12:41 -0400 (EDT) Received: from smtpin09.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 94B9982499B9 for ; Thu, 1 Apr 2021 20:12:41 +0000 (UTC) X-FDA: 77984896122.09.3787103 Received: from mail-ej1-f46.google.com (mail-ej1-f46.google.com [209.85.218.46]) by imf03.hostedemail.com (Postfix) with ESMTP id D77F0C0007C3 for ; Thu, 1 Apr 2021 20:12:39 +0000 (UTC) Received: by mail-ej1-f46.google.com with SMTP id e14so4623126ejz.11 for ; Thu, 01 Apr 2021 13:12:41 -0700 (PDT) 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=9RELdyoJ3mdxBRdi3zE7PaTML6+VOkh57f4y7o9oQPs=; b=BRMEjnbiNfMVhUbUPe/Za+3fa+t9pCHc1P29MuyXNMwWOzN+wZBnSiAUdll2YDL8GG XpZ05cRnYgDf+lO6Dbi3aZD81Yz4L/ZwlkTEW6nlpENXvUO+/4N30VVs8PMyjzJ4gSZp IjDH9sPPe6Lw/5mP570ADeoiwRvDkUTMLu2jQVT2+G/5EOhWKJADcv5JS4EoDcyYtRte YQqpmkJ8zRi8yJmrwLsiXHblu4b8SFAIJJupI08spxpjJNHooIdaa/gsc1SP1qVf5KuP 30Gfn+z7PfZrG+En6KfDSbIimc2GKlZV3TJVCgelE9FRhjCwWzyuiEOjGVViySoBlDNJ ZuCQ== 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=9RELdyoJ3mdxBRdi3zE7PaTML6+VOkh57f4y7o9oQPs=; b=AaXj79BZsxlq5YSfi7hPJTIeZN2F2X912VU2N2aAGWNgheGXbfM7WJ80WDI99u2WEU 9AfYqYh1Deey1XK5AUrJMCrvhFkZxXKFk+DRMy3tX/ouP625jwNMzK8BVRBQ8Agum8dB 12uPZbhmGeX+VsXOFMGeqAWRLDtKkuQq3ht3zmTpR9eWZJdt8Sg+o6mRlL5C8PlaC+yK WFz99CUakUiMmxDEKi3hJMKeSMy473SfwPQyg8/iUV6eI6jEtpJSkDq70YEebLWg07gR Qo+WC2bf1zV2Tyvph11fFL0b84Cdckn6Swgk9R6+6GCeQvwSsIBnif74LRgNb162X17s +r3Q== X-Gm-Message-State: AOAM530sytbonoa84vRR9w2z3zXFrhO6UDgskcsuW+x193hW59zmxGmM sOF7NjUfDzj0lqS2aGXvwiaXr3k0LGYhRLTfJSU= X-Google-Smtp-Source: ABdhPJy8ZU45eCiR5zibHk9azCrqAIUfIh6snXCOXNIXWgzPQn9kWt7iw4FUdAxqMZ3lvaK560nWW8o6XxPXJBiFi5o= X-Received: by 2002:a17:906:bcfc:: with SMTP id op28mr10810124ejb.238.1617307960129; Thu, 01 Apr 2021 13:12:40 -0700 (PDT) MIME-Version: 1.0 References: <20210329183312.178266-1-shy828301@gmail.com> <20210330164200.01a4b78f@thinkpad> <20210331132053.GW15768@suse.de> In-Reply-To: <20210331132053.GW15768@suse.de> From: Yang Shi Date: Thu, 1 Apr 2021 13:12:28 -0700 Message-ID: Subject: Re: [RFC PATCH 0/6] mm: thp: use generic THP migration for NUMA hinting fault To: Mel Gorman Cc: Gerald Schaefer , "Kirill A. Shutemov" , Zi Yan , Michal Hocko , Huang Ying , Hugh Dickins , hca@linux.ibm.com, gor@linux.ibm.com, borntraeger@de.ibm.com, Andrew Morton , Linux MM , linux-s390@vger.kernel.org, Linux Kernel Mailing List , Alexander Gordeev Content-Type: text/plain; charset="UTF-8" X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: D77F0C0007C3 X-Stat-Signature: fa1uw6r7rpnfdtdshmfsxwpe9aycaepu Received-SPF: none (gmail.com>: No applicable sender policy available) receiver=imf03; identity=mailfrom; envelope-from=""; helo=mail-ej1-f46.google.com; client-ip=209.85.218.46 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1617307959-241018 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 Wed, Mar 31, 2021 at 6:20 AM Mel Gorman wrote: > > On Tue, Mar 30, 2021 at 04:42:00PM +0200, Gerald Schaefer wrote: > > Could there be a work-around by splitting THP pages instead of marking them > > as migrate pmds (via pte swap entries), at least when THP migration is not > > supported? I guess it could also be acceptable if THP pages were simply not > > migrated for NUMA balancing on s390, but then we might need some extra config > > option to make that behavior explicit. > > > > The split is not done on other architectures simply because the loss > from splitting exceeded the gain of improved locality in too many cases. > However, it might be ok as an s390-specific workaround. > > (Note, I haven't read the rest of the series due to lack of time but this > query caught my eye). Will wait for your comments before I post v2. Thanks. > > -- > Mel Gorman > SUSE Labs