From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265693AbTFNSCr (ORCPT ); Sat, 14 Jun 2003 14:02:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265697AbTFNSCr (ORCPT ); Sat, 14 Jun 2003 14:02:47 -0400 Received: from snipe.mail.pas.earthlink.net ([207.217.120.62]:25333 "EHLO snipe.mail.pas.earthlink.net") by vger.kernel.org with ESMTP id S265693AbTFNSCq (ORCPT ); Sat, 14 Jun 2003 14:02:46 -0400 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <16107.26375.67524.817817@nv.winux.com> Date: Sat, 14 Jun 2003 14:18:47 -0400 To: linux-kernel@vger.kernel.org From: Larry Auton Subject: direct i/o problem with 2.4.20 and 2.4.21rc7 X-Mailer: VM 7.04 under 21.4 (patch 9) "Informed Management" XEmacs Lucid Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org I have an application that requires direct i/o to thousands of files. On 2.4.19 the open's would eventually fail (at around 7200 files). On 2.4.20 and 2.4.21rc7 the machine hangs. Here's a sample program to do the deed: wget http://www.skarven.net/lda/crashme.c cc -o crashme crashme.c # compile it ./crashme 4000 # OK ./crashme 9999 # CRASH It's a little obfuscated to eliminate the need for root privileges to mess with rlimit. It simply opens a bunch of files with O_DIRECT and, when enough files are open, the system will hang. The system hangs when '/proc/slabinfo' reports that 'kiobuf' reaches just over 7230 active objects. I don't believe that this problem is specific to any particular file system as the failure occurs when using both ext2 and reiserfs. Larry Auton