From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f41.google.com (mail-pa0-f41.google.com [209.85.220.41]) by kanga.kvack.org (Postfix) with ESMTP id 60F786B0032 for ; Mon, 23 Feb 2015 16:03:33 -0500 (EST) Received: by pablf10 with SMTP id lf10so30425589pab.6 for ; Mon, 23 Feb 2015 13:03:33 -0800 (PST) Received: from mga03.intel.com (mga03.intel.com. [134.134.136.65]) by mx.google.com with ESMTP id jc4si12735945pbd.12.2015.02.23.13.03.32 for ; Mon, 23 Feb 2015 13:03:32 -0800 (PST) From: Andi Kleen Subject: Re: [RFC 0/6] the big khugepaged redesign References: <1424696322-21952-1-git-send-email-vbabka@suse.cz> Date: Mon, 23 Feb 2015 13:03:22 -0800 In-Reply-To: <1424696322-21952-1-git-send-email-vbabka@suse.cz> (Vlastimil Babka's message of "Mon, 23 Feb 2015 13:58:36 +0100") Message-ID: <87lhjouyqt.fsf@tassilo.jf.intel.com> MIME-Version: 1.0 Content-Type: text/plain Sender: owner-linux-mm@kvack.org List-ID: To: Vlastimil Babka Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrew Morton , Hugh Dickins , Andrea Arcangeli , "Kirill A. Shutemov" , Rik van Riel , Mel Gorman , Michal Hocko , Ebru Akagunduz , Alex Thorlton , David Rientjes , Peter Zijlstra , Ingo Molnar Vlastimil Babka writes: > This has been already discussed as a good > idea and a RFC has been posted by Alex Thorlton last October [5]. In my opinion it's a very bad idea. It heavily penalizes the single threaded application case, which is quite important. And it would likely lead to even larger latencies on the application base, even for the multithreaded case, as there is no good way anymore to hide blocking latencies in the process. The current single thead khugepaged has various issues, but this would just make it much worse. IMHO it's useless to do much here without a lot of data first to identify the actual problems. Doing things first without analysis first seems totally backwards. -Andi -- ak@linux.intel.com -- Speaking for myself only -- 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