zpool export: umount fails due to gvfsd-trash (Thunar wrongly opened by Firefox)

On 26/11/2020 10:07, Kurt Jaeger wrote:
> Use fstat -- this is part of the base system.
>
> Maybe lsof does not catch every corner case ?
On 26/11/2020 17:34, Gary Palmer wrote:
> does "fuser -c" show anything?
>
> the -m option may also be interesting (Search through mmapped files too)
>
> Regards,
>
> Gary

Thanks.

As far as I can tell the problem occurs only when Thunar, which I rarely 
use, is wrongly opened by Firefox.

KDE Plasma here. I can't recall how to force applications such as 
Firefox to respect my preference for Dolphin.

gvfsd-trash considered harmful
<https://lists.freebsd.org/pipermail/freebsd-gnome/2013-September/029033.html> 


 From htop:

…

   PID USER      PRI  NI  VIRT   RES S CPU% MEM%   TIME+  Command

  4484 grahamper  21   0 39168 12692 S  0.0  0.1  0:00.17    ├─ 
gvfsd-metadata
  4206 grahamper  20   0 37768  8564 S  0.0  0.1  0:00.12    ├─ 
gvfs-gphoto2-volume-monitor
  4201 grahamper  20   0 36548  8188 S  0.0  0.0  0:00.11    ├─ 
gvfs-mtp-volume-monitor
  4184 grahamper  20   0 48072 13168 S  0.0  0.1  0:00.63    ├─ 
gvfs-udisks2-volume-monitor
  4179 grahamper  20   0 40660  8748 S  0.0  0.1  0:00.17    ├─ gvfsd
  7288 grahamper  20   0 45140 10476 S  0.0  0.1  0:00.06    │  ├─ 
gvfsd-dnssd --spawner :1.34 /org/gtk/gvfs/exec_spaw/5
  7285 grahamper  20   0 53520 10016 S  0.0  0.1  0:00.09    │  ├─ 
gvfsd-network --spawner :1.34 /org/gtk/gvfs/exec_spaw/3
  5883 grahamper  20   0 47608  9640 S  0.0  0.1  0:01.07    │  └─ 
gvfsd-trash --spawner :1.34 /org/gtk/gvfs/exec_spaw/2

----

root_at_mowa219-gjp4-8570p:~ # zpool export Transcend
cannot unmount '/Volumes/t500/VirtualBox': umount failed
root_at_mowa219-gjp4-8570p:~ # fstat -f /Volumes/t500/VirtualBox
USER     CMD          PID   FD MOUNT      INUM MODE         SZ|DV R/W
grahampe gvfsd-trash  5883   19 /Volumes/t500/VirtualBox     34 
drwxr-xr-x       7  r
grahampe gvfsd-trash  5883   20 /Volumes/t500/VirtualBox     34 
drwxr-xr-x       7  r
grahampe gvfsd-trash  5883   21 /Volumes/t500/VirtualBox    401 
drwx------       4  r
grahampe gvfsd-trash  5883   22 /Volumes/t500/VirtualBox    403 
drwxr-xr-x       3  r
root_at_mowa219-gjp4-8570p:~ # fuser -c /Volumes/t500/VirtualBox
/Volumes/t500/VirtualBox:
root_at_mowa219-gjp4-8570p:~ # find /Volumes/t500/VirtualBox \( -inum 34 
-or -inum 401 -or -inum 403 \) -print
/Volumes/t500/VirtualBox
/Volumes/t500/VirtualBox/.Trash-1002
/Volumes/t500/VirtualBox/.Trash-1002/files
root_at_mowa219-gjp4-8570p:~ # zfs list /Volumes/t500 /Volumes/t500/VirtualBox
NAME                   USED  AVAIL     REFER  MOUNTPOINT
Transcend              115G   335G       96K  /Volumes/t500
Transcend/VirtualBox   114G   335G      114G /Volumes/t500/VirtualBox
root_at_mowa219-gjp4-8570p:~ #

(My previous over-reliance upon lsof stemmed from familiarity with the 
command on Mac OS X with HFS Plus.)