From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: Re: computing drop-able caches To: Daniel Walker , "Khalid Mughal (khalidm)" , Rik van Riel , Johannes Weiner References: <56AAA77D.7090000@cisco.com> <20160128235815.GA5953@cmpxchg.org> <56AABA79.3030103@cisco.com> <56AAC085.9060509@cisco.com> <20160129015534.GA6401@cmpxchg.org> <56ABEAA7.1020706@redhat.com> <56BB7BC7.4040403@cisco.com> Cc: Alexander Viro , Michal Hocko , Andrew Morton , "linux-fsdevel@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "xe-kernel@external.cisco.com" From: Dave Hansen Message-ID: <56BB7DDE.8080206@intel.com> Date: Wed, 10 Feb 2016 10:13:50 -0800 MIME-Version: 1.0 In-Reply-To: <56BB7BC7.4040403@cisco.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: On 02/10/2016 10:04 AM, Daniel Walker wrote: >> [Linux_0:/]$ echo 3 > /proc/sys/vm/drop_caches >> [Linux_0:/]$ cat /proc/meminfo >> MemTotal: 3977836 kB >> MemFree: 1095012 kB >> MemAvailable: 1434148 kB > > I suspect MemAvailable takes into account more than just the droppable > caches. For instance, reclaimable slab is included, but I don't think > drop_caches drops that part. There's a bit for page cache and a bit for slab, see: https://kernel.org/doc/Documentation/sysctl/vm.txt -- 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 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753191AbcBJSOG (ORCPT ); Wed, 10 Feb 2016 13:14:06 -0500 Received: from mga09.intel.com ([134.134.136.24]:5527 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752742AbcBJSOF (ORCPT ); Wed, 10 Feb 2016 13:14:05 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.22,426,1449561600"; d="scan'208";a="909436286" Subject: Re: computing drop-able caches To: Daniel Walker , "Khalid Mughal (khalidm)" , Rik van Riel , Johannes Weiner References: <56AAA77D.7090000@cisco.com> <20160128235815.GA5953@cmpxchg.org> <56AABA79.3030103@cisco.com> <56AAC085.9060509@cisco.com> <20160129015534.GA6401@cmpxchg.org> <56ABEAA7.1020706@redhat.com> <56BB7BC7.4040403@cisco.com> Cc: Alexander Viro , Michal Hocko , Andrew Morton , "linux-fsdevel@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "xe-kernel@external.cisco.com" From: Dave Hansen Message-ID: <56BB7DDE.8080206@intel.com> Date: Wed, 10 Feb 2016 10:13:50 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.5.1 MIME-Version: 1.0 In-Reply-To: <56BB7BC7.4040403@cisco.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/10/2016 10:04 AM, Daniel Walker wrote: >> [Linux_0:/]$ echo 3 > /proc/sys/vm/drop_caches >> [Linux_0:/]$ cat /proc/meminfo >> MemTotal: 3977836 kB >> MemFree: 1095012 kB >> MemAvailable: 1434148 kB > > I suspect MemAvailable takes into account more than just the droppable > caches. For instance, reclaimable slab is included, but I don't think > drop_caches drops that part. There's a bit for page cache and a bit for slab, see: https://kernel.org/doc/Documentation/sysctl/vm.txt