Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752665AbYCIMEL (ORCPT ); Sun, 9 Mar 2008 08:04:11 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750701AbYCIMD5 (ORCPT ); Sun, 9 Mar 2008 08:03:57 -0400 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:37446 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750840AbYCIMD4 (ORCPT ); Sun, 9 Mar 2008 08:03:56 -0400 Date: Sun, 09 Mar 2008 21:03:35 +0900 From: KOSAKI Motohiro To: Ingo Molnar Subject: Re: quicklists confuse meminfo Cc: kosaki.motohiro@jp.fujitsu.com, Thomas Gleixner , LKML , Linus Torvalds , Andrew Morton , Christoph Lameter , Bart Van Assche In-Reply-To: <20080309111456.GA21690@elte.hu> References: <20080309111456.GA21690@elte.hu> Message-Id: <20080309210000.C6DE.KOSAKI.MOTOHIRO@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: Becky! ver. 2.42 [ja] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1782 Lines: 63 Hi > hm. I think we should not let this much RAM hang around in a > special-purpose allocator like quicklists. Shouldnt the quicklists be > temporary in nature, and be trimmed much more agressively? > > in fact, we have a check_pgt_cache() call in cpu_idle(), which does: > > quicklist_trim(0, pgd_dtor, 25, 16); > > but it appears we dont do quicklist trimming anywhere else! So if a > system has no idle time, the quicklist can grow unbounded, and that's a > real memory leak IMO. I test following method. 1. $ hackbench 100 process 1000 2. $ cat /proc/meminfo quicklist consume 1GB memory of 8GB total memory system. it seems too large cache ;) IMHO we need shrink pgtable cache mecanism. --------------------------------------- MemTotal: 7683328 kB MemFree: 4940672 kB Buffers: 2816 kB Cached: 23232 kB SwapCached: 72192 kB Active: 56832 kB Inactive: 77440 kB SwapTotal: 2031488 kB SwapFree: 1907776 kB Dirty: 704 kB Writeback: 0 kB AnonPages: 48384 kB Mapped: 20864 kB Slab: 1325824 kB SReclaimable: 11968 kB SUnreclaim: 1313856 kB PageTables: 13632 kB NFS_Unstable: 0 kB Bounce: 0 kB CommitLimit: 5873152 kB Committed_AS: 531008 kB VmallocTotal: 17592177655808 kB VmallocUsed: 28864 kB VmallocChunk: 17592177623104 kB Quicklists: 1194304 kB HugePages_Total: 0 HugePages_Free: 0 HugePages_Rsvd: 0 HugePages_Surp: 0 Hugepagesize: 262144 kB -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/