From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from len.romanrm.net ([91.121.75.85]:43224 "EHLO len.romanrm.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932309AbdJZRlv (ORCPT ); Thu, 26 Oct 2017 13:41:51 -0400 Date: Thu, 26 Oct 2017 22:41:48 +0500 From: Roman Mamedov To: Cheyenne Wills Cc: linux-btrfs@vger.kernel.org Subject: Re: Need some assistance/direction in determining a system hang during heavy IO Message-ID: <20171026224148.57e4d035@natsu> In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Thu, 26 Oct 2017 09:40:19 -0600 Cheyenne Wills wrote: > Briefly when I upgraded a system from 4.0.5 kernel to 4.9.5 (and > later) I'm seeing a blocked task timeout with heavy IO against a > multi-lun btrfs filesystem. I've tried a 4.12.12 kernel and am still > getting the hang. There is now 4.9.58 (fifty three versions later!) and 4.12 series is long abandoned and gone from the charts altogether. So just in case, did you check with the latest kernels? Also, keep in mind the 120 second warnings are just that, and not an error condition by themselves. You can disable them or increase the maximum timeout in sysctl settings. And it is not clear from your reports if you only get warnings and after the load subsides everything is back to normal, or the FS locks out "for good", i.e. with all access attempts hanging indefinitely and no way to unmount the FS or otherwise recover. -- With respect, Roman