From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758142AbXK0H1c (ORCPT ); Tue, 27 Nov 2007 02:27:32 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753325AbXK0H1P (ORCPT ); Tue, 27 Nov 2007 02:27:15 -0500 Received: from turing-police.cc.vt.edu ([128.173.14.107]:56537 "EHLO turing-police.cc.vt.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752765AbXK0H1O (ORCPT ); Tue, 27 Nov 2007 02:27:14 -0500 X-Mailer: exmh version 2.7.2 01/07/2005 with nmh-1.2 To: Eric Dumazet Cc: Andrew Morton , Alan Cox , Linux kernel Subject: Re: [PATCH] get rid of NR_OPEN and introduce a sysctl_nr_open In-Reply-To: Your message of "Tue, 27 Nov 2007 08:09:19 +0100." <474BC29F.4060706@cosmosbay.com> From: Valdis.Kletnieks@vt.edu References: <200711200023.lAK0NtEe004292@imap1.linux-foundation.org> <20071120004832.393cc5a8@the-village.bc.nu> <474291E7.5060700@cosmosbay.com> <20071120001411.4db1eb04.akpm@linux-foundation.org> <474420EE.4060603@cosmosbay.com> <20071126201717.450e44eb.akpm@linux-foundation.org> <474BC29F.4060706@cosmosbay.com> Mime-Version: 1.0 Content-Type: multipart/signed; boundary="==_Exmh_1196148356_2790P"; micalg=pgp-sha1; protocol="application/pgp-signature" Content-Transfer-Encoding: 7bit Date: Tue, 27 Nov 2007 02:25:56 -0500 Message-ID: <4651.1196148356@turing-police.cc.vt.edu> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org --==_Exmh_1196148356_2790P Content-Type: text/plain; charset=us-ascii On Tue, 27 Nov 2007 08:09:19 +0100, Eric Dumazet said: > Changing NR_OPEN is not considered safe because of vmalloc space potential > exhaust. Verbiage about this point... > +nr_open > +------- > + > +Denotes the maximum number of file-handles a process can > +allocate. Default value is 1024*1024 (1048576) which should be > +enough for most machines. Actual limit depends on RLIMIT_NOFILE > +resource limit. > + should probably be in here - can you add something of the form "Setting this too high can cause vmalloc failures, especially on smaller-RAM machines", and/or *say* how much RAM the default takes? Sure, it's 1M entries, but my tuning on a 2G-RAM machine will differ if these are byte-sized, or 128-byte sized - one is off in a corner, the other is 1/16th of my entire memory. Also, would it be useful to *lower* the value drastically, if you know a priori that no process should get up to 1K file handles, much less 1M? Does that buy me anything different than setting RLIMIT_NOFILE=1024? --==_Exmh_1196148356_2790P Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (GNU/Linux) Comment: Exmh version 2.5 07/13/2001 iD8DBQFHS8aEcC3lWbTT17ARAl7fAJ9aWzumE0ZgwMMJJPLWU9MHwmmGcQCgxvDC MTSt0wnw4F94gVdK0Gjvyio= =jBe5 -----END PGP SIGNATURE----- --==_Exmh_1196148356_2790P--