unraid overhaul

[Pandemic]

I backed up my entire box and now I'd like to reformat all disks. Ideally I was thinking about preclearing them again just to stress test them. What format is ideal at this point?

[Hoopster]

10 minutes ago, Pandemic said:

What format is ideal at this point?

Usually, array disks are best in XFS format.  Cache pools, depending on how you intend to use them, can be XFS (single disk) or BTRFS (single or multiple disks but usually for multiple disks).

 

There is a ZFS plugin if you really think you want/need ZFS.

[Pandemic]

i dont know enough about the different formats to be honest.

[ChatNoir]

1 hour ago, Pandemic said:

i dont know enough about the different formats to be honest.

Then go for XFS for the Array.

 

If you are using one or several pools, are they single or multiple disks ?

[Pandemic]

by pools, do you mean shares? I've got a few shares using multiple disks.

 

 

[Pandemic]

I'm somewhat perplexed here. I've formatted all disks and cache into XFS and noticed the default used space for that format is 27.9GB whereas the BTRFS is 3.70MB?! That's a pretty massive difference.

[Squid]

There are differences in overhead between filesystems.  But, that 28G would imply that there is a docker image on the drive whereas the cache drive when in BTRFS didn't have the image on it.

[trurl]

2 hours ago, Pandemic said:

by pools, do you mean shares? I've got a few shares using multiple disks.

No

 

Cache is a pool. Additional pools can be created in V6.9+ Each pool can have multiple disks if formatted as btrfs. A pool is treated like a disk for most purposes.

 

Shares can span disks, including pools. Shares are just the combined top level folders on array and pools.

[Pandemic]

I've got one cache drive in XFX and has about 1.08 GB used. Disk 1 is in BTRFS and using 3.7MB and the other disks are in XFS using 27.9GB. I'm just surprised by that.

 

I currently have no shares set up and no pools other than the cache drive.

 

I've redone this box in an effort to set it up more effectively. Are you saying if I wanted a directory that stored large amounts of data it's better to set it up as a pool or a share?

[Squid]

Overhead is overhead and varies according to the size of the drive (and as you've seen file system chosen).  What's the actual percentage of used space?  While your use case may be different, that 27GB to me (not that I've ever looked on a blank drive) would amount to my local coffee shop raising their price by a penny.  Or as a friend of mine once put it: it doesn't matter if you've got $0 or $20 in your pocket - you're still broke, and a drive that get's filled up > 95% isn't going to wind up being very efficient at storing the last 5% files on any system.

[trurl]

11 minutes ago, Pandemic said:

Are you saying if I wanted a directory that stored large amounts of data it's better to set it up as a pool or a share?

Usually you don't work directly with disks or pools, except when installing them or replacing them, etc.

 

"User Shares" is the way you normally access folders and their contents.

 

1 hour ago, trurl said:

Shares can span disks, including pools. Shares are just the combined top level folders on array and pools.

 

User Shares have been part of Unraid for as long as I've been using it, v4.7, and I assume before. You have been a forum member for many years, I assume you understand User Shares.

[Pandemic]

For sure, I just wanted to make sure Shares were the best way to proceed. My NAS uses pools for essentially the same thing as unraid uses shares.

Update is essentially complete. I just have to go down the high water, most free, fill up rabbit hole again.

[trurl]

Really just differences in terminology. In a more generic sense, pools can refer to multiple disks. In that sense, the array is a pool.

 

For Unraid specific terminology, cache is fast storage separate from the parity array, and sometime in early v6 btrfs raid multidisk cache pools were introduced.

 

With Unraid v6.9+, multiple pools were introduced, cache can be one of these, but you can have others named however you want, and you don't even have to have a pool named cache. Each pool can have multiple disk when formatted btrfs.

 

User shares are the combined top level folders on array and all pools. Top level folders of the same name are part of the same user share, so user shares allow folders to span disks.

 

17 minutes ago, Pandemic said:

high water, most free, fill up

Highwater is default for a good reason. It is a compromise that allows all included disks to be used by a share eventually, without constantly switching between disks just because one disk temporarily has more free than another. It is more efficient than most free, which can actually slow things down.