"Not enough space" when there actually is!

[Roger79]

When replacing files larger than remaining space on the drive where these files are placed, I get the "Not enough space" message, even if there are plenty of space on the pool. DP should just delete the old files and place the new ones on a different drive instead.

 

Regards Roger :-)

[Christopher (Drashna)]

The problem is that this isn't that simple.

 

While the pool itself may have enough free space, that ... doesn't really matter.  What matters is if the underlying disks in the pool have enough free space.  As the files themselves are being written to the underlying disks, they need to have enough free space to handle this.  If they don't then you'll definitely see this error. 

 

 

Additionally, one of the big design goals for the software is to avoid doing things "out of the ordinary". Meaning, we want the pool to function as a normal disk, as much as possible, with minimal "special handling" under the hood.  This is in a large part to prevent weird issues, and complications. 

 

 

 

 

That said, if the underlying disks do have enough free space, and you're still seeing this issue, then try enabling file system logging and reproduce the issue:

http://wiki.covecube.com/StableBit_DrivePool_2.x_Log_Collection

[Roger79]

...late reply coming... busy with other things 

 

I know the disks in the pool needs space to write the files. But in cases where the pool consists of many disks, and at least two of them have enough free space to write the file, DP should start writing on these two instead of rewriting on top of the existing file on a "full" disk which causes this error. (that became a long sentence   )

[Christopher (Drashna)]

You're talking about when the files are modified/overwritten, right? 

 

If so, that's ... tricky, at best.  These are generally "modifies", which means that the file isn't moved to a new disk, but the existing data is changed, at least partially.

 

That last bit being important. Meaning that there is no real "safe" way to do this.  You'd need to move the file or create a new one, not modify/overwrite an existing one.   

 

And this has more to do with how the file system handles things, and not the pool specifically.