From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail144.messagelabs.com (mail144.messagelabs.com [216.82.254.51]) by kanga.kvack.org (Postfix) with SMTP id 7C57C6B0085 for ; Tue, 23 Nov 2010 04:44:43 -0500 (EST) Received: by iwn10 with SMTP id 10so1138914iwn.14 for ; Tue, 23 Nov 2010 01:44:42 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <1290501502.2390.7029.camel@nimitz> References: <20101122161158.02699d10.akpm@linux-foundation.org> <1290501502.2390.7029.camel@nimitz> Date: Tue, 23 Nov 2010 10:44:42 +0100 Message-ID: Subject: Re: Sudden and massive page cache eviction From: =?UTF-8?Q?Peter_Sch=C3=BCller?= Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-mm@kvack.org To: Dave Hansen Cc: Andrew Morton , linux-kernel@vger.kernel.org, Mattias de Zalenski , linux-mm@kvack.org List-ID: > You don't have anybody messing with /proc/sys/vm/drop_caches, do you? Highly unlikely given that (1) evictions, while often very significant, are usually not *complete* (although the first graph example I provided had a more or less complete eviction) and (2) the evictions are not obviously periodic indicating some kind of cron job, and (3) we see the evictions happening across a wide variety of machines. So yes, I feel confident that we are not accidentally doing that. (FWIW though, drop_caches is great. I only recently found out about it, and it's really useful when benchmarking.) -- / Peter Schuller aka scode -- 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/ . Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: email@kvack.org