From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9F51BC04AAF for ; Tue, 21 May 2019 19:22:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7120C217D7 for ; Tue, 21 May 2019 19:22:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=permerror (0-bit key) header.d=prgmr.com header.i=@prgmr.com header.b="mUYRxipE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727136AbfEUTWC (ORCPT ); Tue, 21 May 2019 15:22:02 -0400 Received: from mail.prgmr.com ([71.19.149.6]:46906 "EHLO mail.prgmr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726771AbfEUTWC (ORCPT ); Tue, 21 May 2019 15:22:02 -0400 Received: from turtle.mx (96-92-68-116-static.hfc.comcastbusiness.net [96.92.68.116]) (Authenticated sender: adp) by mail.prgmr.com (Postfix) with ESMTPSA id D8D2B28C003 for ; Tue, 21 May 2019 20:19:56 -0400 (EDT) DKIM-Filter: OpenDKIM Filter v2.11.0 mail.prgmr.com D8D2B28C003 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=prgmr.com; s=default; t=1558484397; bh=7LTOX4pUVHPrVGkEgfXC03cYfFx0ZUTYY9bZO8iVEBM=; h=Date:From:To:Subject:References:In-Reply-To:From; b=mUYRxipE7YN2fdGIkGZtdSq475v81ZHdqDQmyYLxwcQj6Oq3Xto0xsVRd6K3/6jvb PA27ElT/RRtGKCa5Sf0KvCFmxX0U7tWNoYzymeQr4b3LSH1YkLoVNwvhHEB1WwhJNZ nXostXVY17GfA+sBUnOmtQ0m3By5r8k8IKM1OuE8= Received: (qmail 27831 invoked by uid 1353); 21 May 2019 19:22:54 -0000 Date: Tue, 21 May 2019 13:22:54 -0600 From: Alan Post To: "linux-nfs@vger.kernel.org" Subject: Re: User process NFS write hang followed by automount hang requiring reboot Message-ID: <20190521192254.GN4158@turtle.email> References: <20190520223324.GL4158@turtle.email> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org On Tue, May 21, 2019 at 03:46:03PM +0000, Trond Myklebust wrote: > > A representative sample of stack traces from hung user-submitted > > processes (jobs). The first here is quite a lot more common than > > the later two: > > > > $ sudo cat /proc/197520/stack > > [<0>] io_schedule+0x12/0x40 > > [<0>] nfs_lock_and_join_requests+0x309/0x4c0 [nfs] > > [<0>] nfs_updatepage+0x2a2/0x8b0 [nfs] > > [<0>] nfs_write_end+0x63/0x4c0 [nfs] > > [<0>] generic_perform_write+0x138/0x1b0 > > [<0>] nfs_file_write+0xdc/0x200 [nfs] > > [<0>] new_sync_write+0xfb/0x160 > > [<0>] vfs_write+0xa5/0x1a0 > > [<0>] ksys_write+0x4f/0xb0 > > [<0>] do_syscall_64+0x53/0x100 > > [<0>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 > > [<0>] 0xffffffffffffffff > > > > Have you tried upgrading to 4.19.44? There is a fix that went in not > too long ago that deals with a request leak that can cause stack traces > like the above that wait forever. > That I haven't tried. I gather you're talking about either or both of: 63b0ee126f7e be74fddc976e Which I do see went in after 4.19.24 (which I've tried) but didn't get in 4.20.9 (which I've also tried). Let me see about trying the 4.19.44 kernel. > By the way, the above stack trace with "nfs_lock_and_join_requests" > usually means that you are using a very small rsize or wsize (less than > 4k). Is that the case? If so, you might want to look into just > increasing the I/O size. > These exports have rsize and wsize set to 1048576. That decision was before my time, and I'll guess this value was picked to match NFSSVC_MAXBLKSIZE. Thank you for your help, -A -- Alan Post | Xen VPS hosting for the technically adept PO Box 61688 | Sunnyvale, CA 94088-1681 | https://prgmr.com/ email: adp@prgmr.com