Hi, this time it's just an optimization idea and not an actual down time scenario, yay!

This is what I want to do:

• I have a typical array and a pool cache setup.

• I like the hard drives to spin down as much as possible when not being used, so the spin down delay is very low (15 minutes).

• I also want to speed up random access for media stored on the array, and spinned down disks add a lot of delay.

• The obvious idea is to make those files live on the pool cache, but the pool cache is not big enough to hold all of them. However they do fit on a single array disk.

• So why not keep those files on a share that prefer a certain disk that will be kept always spinning, while making all other shares avoid filling up that disk unless necessary?

That's where I'm at currently.

I have looked around but don't see much interest in this kinda setup. There was this discussion https://forums.unraid.net/topic/37071-possible-to-prioritize-disk-usage-order-for-share/ but they didn't arrive at an answer. I have tried it myself but Unraid 7 doesn't seem to allow manual prioritizing of fill-up.

I would appreciate any idea for how to accomplish this. Thanks in advance.

Look at this setting right here:

You will have to keep an eye on how full that disk becomes and add a second one at the appropriate time!!! (Should not be a big problem with +20TB drives now available.)

Yeah, that certainly could work. Ideally I would like to automate the setup a bit more though.

Basically I want all shares to write to all disks, but only share "Linux" will try to fill up disk 1 to full before moving to other disks, and other shares will try to fill disk 2-5 before trying disk 1.

7 hours ago, Kagoromo said:

and other shares will try to fill disk 2-5 before trying disk 1.

To state the obvious, for the 'other shares' use the "Exclude disk(s)" setting and set it to disk 1 for those.

There is a Feature Request section on the Forum, you could make a request for what you want there. You really need to think about what you want in this 'feature' as you need a logical set of rules of what happens after disk1 becomes full...

That's fair! I understand that mine is a niche requirement. I will try making a userscript to do what I want on a schedule.

12 minutes ago, Kagoromo said:

I will try making a userscript

Be aware of this problem if you are writing a shell script as you will not see any warning if you use a scipt---

https://forums.unraid.net/topic/58290-copy-data-from-a-disk-share-to-a-user-share/

And this post explains the problem in detail

https://forums.unraid.net/topic/58290-copy-data-from-a-disk-share-to-a-user-share/#findComment-571722

Thank you for the links. This copying files between disks seems to be more perilous than I previously thought.

What do you think about the Unbalance plugin? I have used it a few times before and I was not under the impression that it was unsafe.

It's fine as long as you move disk to disk. Unbalanced does that of course.

Edited November 1, 2025Nov 1 by Kilrah

The problem is copies between a disk (Disk Share) and a User Share --- either direction. Understand the Linnux OS will prevent you from coping a file onto itself. But it does not realize that a copy between a disk and user share can result in that exact situation because the paths are different.

For a disk share---

/mnt/diskX/ShareName/FileName

For a User Share---

/mnt/user/ShareName/FileName

The problem arises when the file physical source location in the User Share is on the very disk where you want do the Disk Share operation. In that case, it results in the file being copied onto itself.

Edited November 1, 2025Nov 1 by Frank1940