From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f198.google.com (mail-pf0-f198.google.com [209.85.192.198]) by kanga.kvack.org (Postfix) with ESMTP id 4EE926B0390 for ; Tue, 4 Apr 2017 18:07:06 -0400 (EDT) Received: by mail-pf0-f198.google.com with SMTP id e126so33567310pfg.3 for ; Tue, 04 Apr 2017 15:07:06 -0700 (PDT) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org. [140.211.169.12]) by mx.google.com with ESMTPS id 31si18687902plk.154.2017.04.04.15.07.05 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 04 Apr 2017 15:07:05 -0700 (PDT) Date: Tue, 4 Apr 2017 15:07:03 -0700 From: Andrew Morton Subject: Re: [PATCH] mm: vmscan: fix IO/refault regression in cache workingset transition Message-Id: <20170404150703.742c49d73921df6369ed3dbd@linux-foundation.org> In-Reply-To: <20170404220052.27593-1-hannes@cmpxchg.org> References: <20170404220052.27593-1-hannes@cmpxchg.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Johannes Weiner Cc: Rik van Riel , Mel Gorman , Michal Hocko , Vladimir Davydov , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com On Tue, 4 Apr 2017 18:00:52 -0400 Johannes Weiner wrote: > Since 59dc76b0d4df ("mm: vmscan: reduce size of inactive file list") > we noticed bigger IO spikes during changes in cache access patterns. > > The patch in question shrunk the inactive list size to leave more room > for the current workingset in the presence of streaming IO. However, > workingset transitions that previously happened on the inactive list > are now pushed out of memory and incur more refaults to complete. > > This patch disables active list protection when refaults are being > observed. This accelerates workingset transitions, and allows more of > the new set to establish itself from memory, without eating into the > ability to protect the established workingset during stable periods. > > Fixes: 59dc76b0d4df ("mm: vmscan: reduce size of inactive file list") > Signed-off-by: Johannes Weiner > Cc: # 4.7+ That's a pretty large patch and the problem has been there for a year. I'm not sure that it's 4.11 material, let alone -stable. Care to explain further? -- 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