Questions around disk spinning, service stopped, Verify after copy

[hegyre]

Hello!

I'm testing the application since 2 days now, and I've been reading a lot of documentation and tips on various locations including this forum, reddit, and the manual.

Still I have a few questions that I was not able to find.

1. When I first installed DrivePool, I saw on the GUI settings (on the title bar) an option "Verify after copy".
Since I'm a bit paranoid (probably as a lot of people here), and since I care about my data to some extend, I've enabled this option via the GUI.
Of course I know it will impact the performance a bit but this is not an issue for me right now.
However a few times later, I went into the JSON settings file and I saw the same option, left to the default (false), and not overrided.
So my question is: What is taking precedence here for the same option? Is it the GUI or the JSON setting?
I can already see that the documentation https://wiki.covecube.com/StableBit_DrivePool_2.x_Advanced_Settings could maybe be improved for this setting telling about the GUI option as well.

2. Then since I have 10 spinning disks and 4 NVMe, I tried to play a bit and created a pool only with NVMe, but I noticed all of my other drives were continuously spinning, which was unusual.
And then I found this thread from... 9 years ago! https://community.covecube.com/index.php?/topic/1674-drivepool-service-making-constant-disk-access/
Telling to disable "BitLocker_PoolPartUnlockDetect" option, which I did, and which worked! No disk spinning anymore.
Still I'm a bit sad that 10 years later after the thread I found, someone like me still struggled on that and that nothing was done here to improve the User Experience, like a warning or even a notice somewhere on the doc or the app, telling that the HDD drives will continuously be polled -and continuously spinning- unless the user manually disable this option.

3. Since I had to restart the service for point 2, I've noticed something else.
Even with the DrivePool service stopped (via services.msc), I still had the pooled drive active and could even write files in there, and the file was apparently properly write on a disk. How is that possible with the service stopped?

4. Since I plan to use SnapRAID along with it (along with DrivePool Scanner but haven't tested it yet), can you tell me what would be the advantage of DrivePool duplication knowing that SnapRAID would restore my files back as well?

Thanks in advance!

[Shane]

1. @Alex does the GUI or JSON take precedence in a conflict?

2. I agree there's a couple of parts of the docs that need updating.

3. DrivePool operates on three levels, driver (handles direct file operations) and service (handles balancing, consistency and other scheduled tasks) and GUI (handles the user actions like adding disks, creating pools, etc). The GUI relies on the service which relies on the driver. There's also a command line tool (dpcmd, must be run as administrator) that can talk to the driver (but can only do a small subset of things the GUI can do plus a few others).

4. The advantage of using DrivePool's duplication if you're using SnapRAID is that your entire pool would remain readable during one or more disk failures (depending on how you've organised your disks) without needing to rebuild from the latter's parity, and you can resume writing as soon as you drop the bad disk. The disadvantage of doing so is of course any additional parity computation overhead (depending, ditto) and the additional storage consumption (since every file will take up twice as much - or whatver duplication multiplier you've set - of the available space in the pool, assuming a basic implementation).

[hegyre]

Thanks a lot for your answers, very much appreciated!

Waiting for point 1