Cannot use ZFS ZVOL

[flotpg]

Hey,

as the warning is very clear ;) I thought it would be possible to use a zvol as I didn't find any option to use a file to test (like you do with fio)
"!!!Attention!!!
All data on /dev/sdXXX will be lost!"

Is it possible to use zvol?

➜ TKperf git:(master) ✗ sudo tkperf hdd tank /dev/zvol/tank/tkperf-zvol -nj 2 -iod 16 -rfb You are not using a valid device or partition!

[onitake]

The relevant code is here: https://github.com/thomas-krenn/TKperf/blob/master/src/perfTest/Devices.py#L233-L248
To make the test succeed, the device needs to be listed in /proc/partitions.

That being said, I think you can also use the --force_test parameter to disable the sanity checks.

Perhaps it may also be a good idea to add a dedicated ZVol driver, like there is for Linux md RAID and LSI controllers.

[flotpg]

Hey @onitake, I will give that a try, thx.

[gschoenberger]

THX for your comments!
If we implement a dedicated ZVol device to test, we need commands to:

• Check if a ZVol is available and/not mounted (like the test with /proc/partitions)
• Secure Erase a ZVol
• Read info about a ZVol
  Can you provide those commands?

[flotpg]

You could grep the output of 'zfs mount' which lists currently mounted datasets, not sure how to tell with zvols.
I don't know secure erase commands except of creating an encrypted one from the beginning.
zfs get all tank/tkperf-zvol lists you all infos about the zvol