There is not enough space...

[Jaybau]

I'm getting a "There is not enough space" error trying to copy a file from Windows to Unraid share.

 

For some reason Unraid is filling up Disk 1, but won't use Disk 2.

 

 

 

In the Share Settings, the Minimum free space was 0KB, and I changed it to 500MB. 

I would expect Unraid to start using Disk 2 because there is only 209KB free on Disk 1.

 

 

I cannot provide a Diagnostics file, because Unraid is stuck on "Downloading"

Edited July 15, 2022 by Jaybau

[JorgeB]

Minimum free space should be set to twice the largest file you expect to copy to that share, or you'll get ENOSPC.

[Jaybau]

Still no success.  I set the Minimum Free Space to 1.5 GB for a 370 MB file.

 

 

[Jaybau]

Finally got it to work.  I was overwriting a file.  Overwriting a file did not work.  I had to delete the file.  I also had to wait longer than expected for the file to be deleted.  If I didn't wait long enough, the file would instantly reappear when trying to copy.  Once deleted, and I wait for < 1 minute, I could copy the file.

 

I don't know if the splitting is working as expected.  Not only did I run out of space, but it left partial files on the target.  Those files could not be overwritten (run out of storage errors).  

 

My guess is Unraid doesn't reallocate when overwriting files, even when the Minimum Free Space changes.  And since the existing files were partial files, they would never get reallocated to the disk with free space.  Unraid would just keep trying to writing the same file to the same disk, therefore get the same error.  To resolve this, it requires manually deleting the file.

 

[JorgeB]

11 hours ago, Jaybau said:

My guess is Unraid doesn't reallocate when overwriting files, even when the Minimum Free Space changes.

That's correct, any overwrites will be done in the existing disk.

[trurl]

18 hours ago, Jaybau said:

only 209KB free

This is just asking for trouble.

 

Why are you using fillup allocation anyway?

[Jaybau]

6 hours ago, trurl said:

Why are you using fillup allocation anyway?

 

When I first started with Unraid I wasn't sure of:

 

✔ 1)  If I was going to stay with Unraid.  (though numerous posts about parity errors/recovery make me nervous)

 

✔ 2)  Wasn't completely sure how Unraid was going to work, and I wanted to see how it worked. 

 

3)  Which file system I was going to use.  Still thinking about going back to BTRFS because I now have UPS, don't use BTRFS RAID features ("write hole"), no frequent file changes in case of an OS failure, and I really like how BTRFS does the scrubs (Dynamix File Integrity gives me false positives).  

 

 

[trurl]

You should not attempt to completely fill any disk. Filesystem repair needs some space to work in if you ever need that.

[datruedave]

On 7/16/2022 at 4:00 PM, trurl said:

You should not attempt to completely fill any disk. Filesystem repair needs some space to work in if you ever need that.

How much space does it need?  I'm getting low disk space notifications that my 10TB drives only have 300GB or 400GB free, which seems like a lot of overhead space to me.  I'm upgrading one of my 4TB drives to an 18TB right now (mostly so I can convert my Reiser drives to XFS).  Should I worry about keeping more free space per drive?  Does it need a certain amount of space, or a certain percentage of space?

[JonathanM]

1 hour ago, datruedave said:

How much space does it need?

Probably depends on the type and extent of the damage that needs to be repaired.

1 hour ago, datruedave said:

Does it need a certain amount of space, or a certain percentage of space?

Unknown to me, but we've seen file system repairs fail because of lack of free space, so we warn users not to fill up drives.

 

Another good reason NOT to fill up drives completely is

1 hour ago, datruedave said:

convert my Reiser drives to XFS

new file systems tend towards more robust or more feature filled file systems, which means each file needs more space for the file system to manage it. It's very common for data that fit on a ReiserFS drive be too large to fit on that same drive formatted with a current version of XFS.

[trurl]

Also full disks can perform poorly

[mathomas3]

I currently run 8tb drives... and from the start I have always used fill-up with 100gb min free space... 

 

it's been working well for me... just to give you an example

[datruedave]

21 hours ago, trurl said:

Also full disks can perform poorly

Yeah, I just never considered a disk with 400GB of free space to be "full."  Everything's still working fine, but UnRaid is giving me low disk space warnings.  I've been ignoring them, but now I'm wondering if I should take them more seriously.

[trurl]

45 minutes ago, datruedave said:

never considered a disk with 400GB of free space to be "full." 

Of course not. But

On 7/15/2022 at 1:49 PM, Jaybau said:

only 209KB free on Disk 1

is too full.

 

Minimum Free is only one thing Unraid considers when choosing a disk for a file. If a file already exists, it is going to be overwritten on the disk it is already on, regardless of anything else including whether or not the changed file will fit.

 

Split Level takes precedence over Minimum Free. And of course Include or Exclude can prevent another disk being chosen.

 

Personally, I always just use default Highwater allocation, and if I want a share to go mostly to one disk I use Include to make that happen. Then long before that disk gets close to full, I include other disks for the share to use.

 

Lots of settings provide lots of ways to keep disks from getting too full.

 

 

 

[ConnerVT]

58 minutes ago, datruedave said:

Yeah, I just never considered a disk with 400GB of free space to be "full." 

 

But then, for an 8TB drive, that would be 95% full.

 

Then you need to consider the size of files that potentially will be added.  A full system monthly backup of my desktop PC is over 1TB.  A Remux 4K movie sometimes can approach that 400GB size.

[trurl]

7 minutes ago, ConnerVT said:

A Remux 4K movie sometimes can approach that 400GB size.

and so you should set Minimum Free accordingly

 

[Jaybau]

On 7/19/2022 at 8:11 AM, JonathanM said:

new file systems tend towards more robust or more feature filled file systems, which means each file needs more space for the file system to manage it.

 

I would have guessed the required storage would be pre-allocated when formatted.

 

I also noticed a big difference in initial storage consumption between BTRFS and XFS.  XFS took a lot more space.

 

I wouldn't mind learning why XFS needs more space than BTRFS. Not sure if CoW is more efficient than journal, or what presumably makes XFS more robust.

[JonathanM]

2 hours ago, Jaybau said:

 

I would have guessed the required storage would be pre-allocated when formatted.

To some extent yes, however, it would be wasteful to assume a file system would hold a millions of files, when it's entirely likely a media drive would only have hundreds. Different file systems have different strategies to account for this kind of variability.

[datruedave]

On 7/20/2022 at 8:29 AM, ConnerVT said:

 

But then, for an 8TB drive, that would be 95% full.

Right.  I guess I wish there was a way to make the notifications based on actual space instead of (or in addition to) a percentage.  5% free space on my 18TB drives is a LOT of space.  Way more (it seems to me anyway) than needed for overhead.  5% free space on a 500GB drive is a different story.  I don't know what kind of overhead Unraid needs to be happy, but 900GB (5% of 18TB) seems excessive.

So, I've just been taking the low disk notifications with a grain of salt, but I do wonder what level of free space is actually needed.

[trurl]

You can set those thresholds per disk by clicking on a disk to get to its settings