From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ie0-f179.google.com (mail-ie0-f179.google.com [209.85.223.179]) by kanga.kvack.org (Postfix) with ESMTP id EF21A6B0038 for ; Thu, 12 Feb 2015 19:59:02 -0500 (EST) Received: by iecrp18 with SMTP id rp18so837315iec.9 for ; Thu, 12 Feb 2015 16:59:02 -0800 (PST) Received: from nm44-vm7.bullet.mail.ne1.yahoo.com (nm44-vm7.bullet.mail.ne1.yahoo.com. [98.138.120.247]) by mx.google.com with ESMTPS id rs7si2558646igb.46.2015.02.12.16.58.57 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 12 Feb 2015 16:59:02 -0800 (PST) Date: Fri, 13 Feb 2015 00:52:56 +0000 (UTC) From: Cheng Rk Reply-To: Cheng Rk Message-ID: <1918343840.1970155.1423788776414.JavaMail.yahoo@mail.yahoo.com> Subject: How to controll Buffers to be dilligently reclaimed? MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: "linux-mm@kvack.org" Hi, I have a system that application is doing a loop on top of block device, (which I think is stupid,) as more and more memory goes into Buffers, then applications started to get -ENOMEM or be oom-killed later (depends on vm.overcommit_memory setting) In this case, if I do a manual reclaim (echo 3 > /proc/sys/vm/drop_caches) I see 90+% of the Buffers is reclaimable, but why it's not reclaimed to fullfill applications' memory allocation request? -bash-4.2$ sudo losetup -a /dev/loop0: [0005]:16512 (/dev/dm-2) -bash-4.2$ free -m total used free shared buffers cached Mem: 48094 46081 2012 40 40324 2085 -/+ buffers/cache: 3671 44422 Swap: 8191 5 8186 I've tried sysctl mm.vfs_cache_pressure=10000 but that seems working to Cached memory, I wonder is there another sysctl for reclaming Buffers? Thanks, - Derek -- 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