suspend/resume versus OpenZFS on USB

[Graham Perrin]

On 12/09/2020 03:09, Graham Perrin wrote:
> … If the pool is ONLINE and imported at suspend time – and if not 
> actively writing to the device at suspend time …

Testing more aggressively (still with a low spec USB flash drive), 
attempting to suspend _immediately after_ writes to the file system.

Second test:

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root at momh167-gjp4-8570p:~ # date ; uptime ; uname -v ; zfs version
Sat Sep 12 04:13:07 BST 2020
  4:13AM  up 8 mins, 5 users, load averages: 0.95, 0.60, 0.30
FreeBSD 13.0-CURRENT #64 r365364: Sun Sep  6 01:38:18 BST 2020 
root at momh167-gjp4-8570p:/usr/obj/usr/src/amd64.amd64/sys/GENERIC-NODEBUG
zfs-0.8.0-1
zfs-kmod-0.8.0-1
root at momh167-gjp4-8570p:~ # zpool status usb ; zfs get mountpoint usb
   pool: usb
  state: ONLINE
   scan: scrub repaired 0B in 00:00:01 with 0 errors on Sat Sep 12 
03:20:51 2020
config:

         NAME        STATE     READ WRITE CKSUM
         usb         ONLINE       0     0     0
           da0p1     ONLINE       0     0     0

errors: No known data errors
NAME  PROPERTY    VALUE         SOURCE
usb   mountpoint  /Volumes/usb  local
root at momh167-gjp4-8570p:~ # du -hs 
/usr/home/grahamperrin/Videos/palmtree.mp4
  68M    /usr/home/grahamperrin/Videos/palmtree.mp4
root at momh167-gjp4-8570p:~ # gdd status=progress bs=1M 
if="/usr/home/grahamperrin/Videos/palmtree.mp4" 
of="/Volumes/usb/palmtree.mp4" ; date ; acpiconf -s3

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In both tests: suspend failed, it was necessary to force off the computer.

Photographs of the second test: 
<https://photos.app.goo.gl/5WRVrCRioCEwnmUg6>