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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 5ECD4C00307 for ; Mon, 9 Sep 2019 08:37:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2B657218DE for ; Mon, 9 Sep 2019 08:37:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1568018273; bh=GjgUbAl+8cSgItftvkqoe8nHYZFMxY6vVOd1KZnsvI8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=FEtj0Vt3ffzJ4Tc0kfm4Ai9a5rQ0KBHAWHNBi+k6msYMF1+PSKTCnCou2k7YFZhYS xRxx7p47igUiFeIT2ZaBL0WIroQr/uCIOWmipCw/4Qbxsyf1atlBgs9K6XgiGe4NiO 4ujYyOOXwCYHFy3bfXNLFfF0Fl7GVevRhiJ/YJ7Y= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389369AbfIIIhw (ORCPT ); Mon, 9 Sep 2019 04:37:52 -0400 Received: from mx2.suse.de ([195.135.220.15]:47682 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727003AbfIIIht (ORCPT ); Mon, 9 Sep 2019 04:37:49 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id E10FFAC37; Mon, 9 Sep 2019 08:37:47 +0000 (UTC) Date: Mon, 9 Sep 2019 10:37:47 +0200 From: Michal Hocko To: David Rientjes Cc: Vlastimil Babka , Linus Torvalds , Andrew Morton , Andrea Arcangeli , Mel Gorman , "Kirill A. Shutemov" , Linux List Kernel Mailing , Linux-MM Subject: Re: [patch for-5.3 0/4] revert immediate fallback to remote hugepages Message-ID: <20190909083747.GD27159@dhcp22.suse.cz> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun 08-09-19 13:45:13, David Rientjes wrote: > If the reverts to 5.3 are not > applied, then I'm not at all confident that forward progress on this issue > will be made: David, could you stop this finally? I think there is a good consensus that the current (even after reverts) behavior is not going all the way down where we want to get. There have been different ways forward suggested to not fallback to remote nodes too easily, not to mention a specialized memory policy to explicitly request the behavior you presumably need (and as a bonus it wouldn't be THP specific which is even better). You seem to be deadlocked in "we've used to do something for 4 years so we must preserve that behavior". All that based on a single and odd workload which you are hand waving about without anything for the rest of the community to reproduce. Please try to get out of the argumentation loop. We are more likely to make a forward progress. 5.3 managed to fix the worst case behavior, now let's talk about more clever tuning. You cannot expect such a tuning is an overnight work. This area is full of subtle side effects and few liners might have hard to predict consequences. -- Michal Hocko SUSE Labs