I'm using one of my UnRAID servers as a file server. It stores a mixture of photos and documents. For the documents, I'd like to try to make the server as responsive as possible. I understand I could use an SSD cache drive to speed up the perceived write times but how can I speed up the read times?

 

If I setup a second SSD as one of the array disks, and set the documents user share to only use this drive would this work? It's mainly the spin up times I am trying to avoid, so if the parity drive was still an HDD would this have to be spun up before the documents could be read from the SSD?

When strictly reading files the parity drive is not used at all

As a follow up question: is it a problem to have a BTRFS formatted drive in array with XFS drives?

As a follow up question: is it a problem to have a BTRFS formatted drive in array with XFS drives?

unRAID currently allows you to have Reiserfs, XFS and BTRFS formatted drives in the array in any combination you want.

Thanks for the replies. So my plan should work then?

Whether an array drive is an SSD or not isn't going to make a huge difference in read times unless, as you noted, the drive is spun down.    Why not just pick one array drive for the share where you store the frequently used documents, and change the spin-down settings for that drive, so it's typically not spun down during your working hours?

 

I would go with what Gary suggested. Try setting the spindown time to 3 hours or something. It should stay spinning all day if it's actually being used. Will just be that first access in the morning which will be delayed but you could setup something to poll the drive in advance to spin it up. Theres probably also a plugin or two that would let you set specific times (though I'm not positive about this)