Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751096AbbHAEVZ (ORCPT ); Sat, 1 Aug 2015 00:21:25 -0400 Received: from mail-pa0-f42.google.com ([209.85.220.42]:33298 "EHLO mail-pa0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750901AbbHAEVX (ORCPT ); Sat, 1 Aug 2015 00:21:23 -0400 Date: Fri, 31 Jul 2015 21:20:26 -0700 (PDT) From: Hugh Dickins X-X-Sender: hugh@eggly.anvils To: Linus Torvalds cc: Hugh Dickins , "J. Bruce Fields" , Dominique Martinet , Dominique Martinet , David Howells , Al Viro , Linux Kernel Mailing List , linux-fsdevel Subject: Re: v4.2-rc dcache regression, probably 75a6f82a0d10 In-Reply-To: Message-ID: References: User-Agent: Alpine 2.11 (LSU 23 2013-08-11) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1463 Lines: 32 On Fri, 31 Jul 2015, Hugh Dickins wrote: > On Fri, 31 Jul 2015, Linus Torvalds wrote: > > > > So leave it running a while longer, but maybe it's 4bf46a272647 like > > Dominique suspects. Although I don't see how that could trigger > > anything either.. > > I restarted with a slightly different version of the load this > morning, which has sometimes shown the issue more easily - I thought > it better to restart with a variant than persist with a run that > might have settled into a protected pattern. We'll see what that > shows later on. It showed nothing useful to this discussion: after an hour and a half it had hung on some almost-certainly-unrelated issue that I've never seen before - looked as if a jbd2 transaction never completed, some tasks waiting for that, some waiting for f_pos_lock held by those (which I hit when I tried to tail the output log). Worry about that another time, if it ever shows up again. I think I'll try reinstating Al's commit, and hacking out that change of David's in dentry_iput() that worried me (though the "especially problematic" remark in his change description suggests that it is an intentional and necessary change to suit unionmount). See how that goes. Hugh -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/