From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay3.corp.sgi.com [198.149.34.15]) by oss.sgi.com (Postfix) with ESMTP id B7C607F3F for ; Mon, 23 Sep 2013 16:26:04 -0500 (CDT) Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by relay3.corp.sgi.com (Postfix) with ESMTP id 5534EAC003 for ; Mon, 23 Sep 2013 14:26:01 -0700 (PDT) Received: from mail-qc0-f182.google.com (mail-qc0-f182.google.com [209.85.216.182]) by cuda.sgi.com with ESMTP id QKZcGO6jX1v06bar (version=TLSv1 cipher=RC4-SHA bits=128 verify=NO) for ; Mon, 23 Sep 2013 14:26:00 -0700 (PDT) Received: by mail-qc0-f182.google.com with SMTP id n4so2566335qcx.13 for ; Mon, 23 Sep 2013 14:25:59 -0700 (PDT) Message-ID: <5240B1DE.5060802@gmail.com> Date: Mon, 23 Sep 2013 17:25:50 -0400 From: "Michael L. Semon" MIME-Version: 1.0 Subject: Re: [PATCH] [RFC] xfs: lookaside cache for xfs_buf_find References: <1378690396-15792-1-git-send-email-david@fromorbit.com> <52404D7F.1080308@sgi.com> In-Reply-To: <52404D7F.1080308@sgi.com> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Mark Tinguely Cc: xfs@oss.sgi.com On 09/23/2013 10:17 AM, Mark Tinguely wrote: > On 09/08/13 20:33, Dave Chinner wrote: >> From: Dave Chinner >> >> CPU overhead of buffer lookups dominate most metadata intensive >> workloads. The thing is, most such workloads are hitting a >> relatively small number of buffers repeatedly, and so caching >> recently hit buffers is a good idea. >> > ... > > I think this needs more testing. > > I get the following panic in a loop test after a few (3-8) iterations: > > while true > do > tar zxpf xfs.tar > cd xfs > make > make modules > cd .. > rm -r xfs > done > > > BUG: unable to handle kernel paging request at ffff880831c1d218 > IP: [] _xfs_buf_find_lookaside+0x98/0xb0 [xfs] > PGD 1c5d067 PUD 85ffe0067 PMD 85fe51067 PTE 8000000831c1d060 > Oops: 0000 [#1] SMP DEBUG_PAGEALLOC > Modules linked in: xfs(O) e1000e exportfs libcrc32c ext3 jbd [last unloaded: xfs > ] > CPU: 0 PID: 23423 Comm: tar Tainted: G O 3.11.0-rc1+ #3 > task: ffff880837f087a0 ti: ffff880831c46000 task.ti: ffff880831c46000 > RIP: 0010:[] [] _xfs_buf_find_lookaside+0x9 > 8/0xb0 [xfs] > RSP: 0018:ffff880831c47918 EFLAGS: 00010286 > RAX: ffff880831c1d200 RBX: ffff8808372e0000 RCX: 0000000000000003 > RDX: 0000000000000011 RSI: 00000000000009c0 RDI: ffff8808372e0000 > RBP: ffff880831c47938 R08: ffff8808372e0000 R09: ffff8808376e8d80 > R10: 0000000000000010 R11: 00000000000009c0 R12: 00000000000009c0 > R13: 0000000000000010 R14: 0000000000000001 R15: 00000000000009c0 > FS: 00007fa4bc51f700(0000) GS:ffff88085bc00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: ffff880831c1d218 CR3: 000000082ed00000 CR4: 00000000000007f0 > Stack: > ffff880831c47938 ffff880831c47aa8 0000000000000010 ffff880834ab7900 > ffff880831c479b8 ffffffffa018a679 ffff8808372e00c0 ffff88082eed01a0 > 0000000000000029 ffff8808372e01f0 0000000000000000 000200015bfe1c68 > Call Trace: > [] _xfs_buf_find+0x159/0x520 [xfs] > [] xfs_buf_get_map+0x30/0x130 [xfs] > [] xfs_buf_read_map+0x26/0xa0 [xfs] > [] xfs_trans_read_buf_map+0x16d/0x4c0 [xfs] > [] xfs_imap_to_bp+0x6c/0x120 [xfs] > [] xfs_iread+0x75/0x2f0 [xfs] > [] ? inode_init_always+0xfb/0x1c0 > [] xfs_iget_cache_miss+0x5a/0x1e0 [xfs] > [] xfs_iget+0x13b/0x1c0 [xfs] > [] xfs_ialloc+0xbd/0x860 [xfs] > [] xfs_dir_ialloc+0x97/0x2e0 [xfs] > [] ? xfs_trans_reserve+0x308/0x310 [xfs] > > I got the same panic running xfstest 319 with the patch at: > http://oss.sgi.com/archives/xfs/2013-09/msg00578.html > once it hung on a xfs_buf lock before the panic. > > And these are the only tests that I threw at this patch. > > --Mark. I got similar issues in full runs of xfstests, but I'm having severe setup problems here and also had to adjust the patch for 32-bit x86. Thanks for reproducing the problem on 64-bit Linux. Michael _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs