From mboxrd@z Thu Jan 1 00:00:00 1970 From: L A Walsh Subject: Re: Bug? or normal behavior? if bug, then where? overlay, vfs, xfs, or ???? Date: Sun, 05 Nov 2017 01:17:22 -0700 Message-ID: <59FEC912.4000005@tlinx.org> References: <59FA4499.2030502@tlinx.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from ishtar.tlinx.org ([173.164.175.65]:54364 "EHLO Ishtar.sc.tlinx.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750932AbdKEIR2 (ORCPT ); Sun, 5 Nov 2017 03:17:28 -0500 In-Reply-To: Sender: linux-unionfs-owner@vger.kernel.org List-Id: linux-unionfs@vger.kernel.org To: Amir Goldstein Cc: overlayfs Amir Goldstein wrote: > > >> I then created a new xfs file system and mounted it on '/edge'; >> >> Ishtar:/edge> xfs_info . >> meta-data=/dev/Data/Edge isize=256 agcount=32, >> agsize=16777200 blks = sectsz=4096 attr=2 >> data = bsize=4096 blocks=536870400, imaxpct=5 >> = sunit=16 swidth=64 blks >> naming =version 2 bsize=4096 ascii-ci=0 >> log =internal bsize=4096 blocks=262143, version=2 >> = sectsz=4096 sunit=1 blks, lazy-count=1 >> realtime =none extsz=4096 blocks=0, rtextents=0 >> >> > > Your problem is that you do not have "ftype" feature in directory > name format, like this: > > naming =version 2 bsize=4096 ascii-ci=0 ftype=1 > > Perhaps you have an old version of mkfs.xfs, not sure when > ftype=1 became the default format, but you can try to > mkfs.xfs -n ftype=1 > ---- Ah... no .. last I was told, if you turned on ftype=1, you had to also pull in crc'ing of all the meta-info. That has problems -- causes errors where there would be no problem, and was never tested on mature file systems that were already fragmented. Do you know if it was separated from crc32 -- for some inexplicable reason, if you wanted ftype, then the crc option would be forced on for you. I didn't want it as I didn't want it to flag errors in metadata that wasn't crucial and didn't want the speed slowdown. Sigh. The problem on crc'ing the meta data, is that there is ALOT more meta data where detecting it will do more harm than good (like what nanosecond the file was last changed, for example). I first ran into it taking the disk offline when I changed the guid on a newly formatted disk. That was fixed, but that was a warning shot... How annoying. From what you say, though only the upper layer needs to have the ftype=1. That's a new filesystem, so shouldn't make that much difference, but the lower fs's I'd want to use overlays with are older file systems. But it sounds like those can remain as they are? (assuming they don't become upper layers in some multi-layer scenario)...