From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f71.google.com (mail-wm0-f71.google.com [74.125.82.71]) by kanga.kvack.org (Postfix) with ESMTP id 812916B0069 for ; Fri, 21 Oct 2016 11:12:44 -0400 (EDT) Received: by mail-wm0-f71.google.com with SMTP id d199so115277wmd.0 for ; Fri, 21 Oct 2016 08:12:44 -0700 (PDT) Received: from mail-wm0-f65.google.com (mail-wm0-f65.google.com. [74.125.82.65]) by mx.google.com with ESMTPS id t2si4127514wmb.23.2016.10.21.08.12.43 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 21 Oct 2016 08:12:43 -0700 (PDT) Received: by mail-wm0-f65.google.com with SMTP id d128so21686wmf.0 for ; Fri, 21 Oct 2016 08:12:43 -0700 (PDT) Date: Fri, 21 Oct 2016 17:12:41 +0200 From: Michal Hocko Subject: Re: [PATCH] shmem: avoid huge pages for small files Message-ID: <20161021151241.GP6045@dhcp22.suse.cz> References: <20161017145539.GA26930@node.shutemov.name> <20161018142007.GL12092@dhcp22.suse.cz> <20161018143207.GA5833@node.shutemov.name> <20161018183023.GC27792@dhcp22.suse.cz> <20161020103946.GA3881@node.shutemov.name> <20161020224630.GO23194@dastard> <20161021020116.GD1075@tassilo.jf.intel.com> <20161021050118.GR23194@dastard> <20161021150007.GA13597@node.shutemov.name> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20161021150007.GA13597@node.shutemov.name> Sender: owner-linux-mm@kvack.org List-ID: To: "Kirill A. Shutemov" Cc: Dave Chinner , Andi Kleen , Hugh Dickins , "Kirill A. Shutemov" , Andrea Arcangeli , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org On Fri 21-10-16 18:00:07, Kirill A. Shutemov wrote: > On Fri, Oct 21, 2016 at 04:01:18PM +1100, Dave Chinner wrote: [...] > > None of these aspects can be optimised sanely by a single threshold, > > especially when considering the combination of access patterns vs file > > layout. > > I agree. > > Here I tried to address the particular performance regression I see with > huge pages enabled on tmpfs. It doesn't mean to fix all possible issues. So can we start simple and use huge pages on shmem mappings only when they are larger than the huge page? Without any tunable which might turn out to be misleading/wrong later on. If I understand Dave's comments it is really not all that clear that a mount option makes sense. I cannot comment on those but they clearly show that there are multiple points of view here. -- Michal Hocko SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org