From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263582AbTDDAJu (for ); Thu, 3 Apr 2003 19:09:50 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263584AbTDDAJu (for ); Thu, 3 Apr 2003 19:09:50 -0500 Received: from e4.ny.us.ibm.com ([32.97.182.104]:53982 "EHLO e4.ny.us.ibm.com") by vger.kernel.org with ESMTP id S263582AbTDDAJp convert rfc822-to-8bit (for ); Thu, 3 Apr 2003 19:09:45 -0500 Content-Type: text/plain; charset=US-ASCII From: Badari Pulavarty To: Andrew Morton Subject: Re: mounting 4000 disks Date: Thu, 3 Apr 2003 16:19:01 -0800 User-Agent: KMail/1.4.1 Cc: linux-kernel@vger.kernel.org References: <200304031520.52138.pbadari@us.ibm.com> <20030403154314.7b8604c9.akpm@digeo.com> In-Reply-To: <20030403154314.7b8604c9.akpm@digeo.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Message-Id: <200304031619.01424.pbadari@us.ibm.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thursday 03 April 2003 03:43 pm, Andrew Morton wrote: > Badari Pulavarty wrote: > > Hi, > > > > I have been playing with testing 4000 disk support. (using 32bit dev_t). > > > > I created 4000 disks using scsi_debug and mounted them. > > We consumed 84MB of low memory by just mouting 4000 filesystems. > > Out of 84MB lowmem 48MB is in slabs. 33 MB is used by buffers. > > 20 kbytes per disk+filesystem seems reasonable. > > The "Buffers" will be the superblock (4k) and the group descriptor blocks > (256 bytes per gigabyte of disk). These are pinned memory. > > And the ext2 superblock got bigger in -mm due to the recent scalability > patches. > > What is using the "size-8192" allocation there? It could be the ext2 > superblock if you have NR_CPUS=32. I think so.. Apr 3 17:21:46 elm3b78 kernel: [] kmalloc+0x5b/0x1d0 Apr 3 17:21:46 elm3b78 kernel: [] vsnprintf+0x2a2/0x430 Apr 3 17:21:46 elm3b78 kernel: [] ext2_fill_super+0x2b/0x8f0 Apr 3 17:21:46 elm3b78 kernel: [] snprintf+0x19/0x20 Apr 3 17:21:46 elm3b78 kernel: [] __bdevname+0xc8/0x110 Apr 3 17:21:46 elm3b78 kernel: [] get_sb_bdev+0xe0/0x130 Apr 3 17:21:46 elm3b78 kernel: [] alloc_vfsmnt+0x79/0xb0 Apr 3 17:21:46 elm3b78 kernel: [] real_lookup+0x5e/0xd0 Apr 3 17:21:46 elm3b78 kernel: [] ext2_get_sb+0x1e/0x30 Apr 3 17:21:46 elm3b78 kernel: [] ext2_fill_super+0x0/0x8f0 Apr 3 17:21:46 elm3b78 kernel: [] do_kern_mount+0x44/0xc0 Apr 3 17:21:46 elm3b78 kernel: [] do_add_mount+0x79/0x170 Apr 3 17:21:46 elm3b78 kernel: [] error_code+0x2d/0x38 Apr 3 17:21:46 elm3b78 kernel: [] do_mount+0x14b/0x170 Apr 3 17:21:46 elm3b78 kernel: [] copy_mount_options+0x73/0xd0 Apr 3 17:21:46 elm3b78 kernel: [] sys_mount+0xed/0x180 Apr 3 17:21:46 elm3b78 kernel: [] syscall_call+0x7/0xb