High Water Table (split any directory as needed)

[sanfark]

Hello can somebody explain the behavior that I am seeing?

 

 

I have a large 3.5TB torrent downloading but for some reason disk2 keeps filling up. I still have 1.75TB left to download and I am concerned disk2 will fill right up and the torrent will fail.

 

Should the writing not have switched to disk3 already with 1.15TB left to create a more equalized data distribution?

 

[JorgeB]

If the files were preallocated, with torrents they can be, they would all be allocated to disk2, so then it would write them all files there.

[sanfark]

1 hour ago, JorgeB said:

If the files were preallocated, with torrents they can be, they would all be allocated to disk2, so then it would write them all files there.

Thanks JorgeB. Two follow up questions:

 

1. Will this cause the disk to "Become full" and the torrent will fail or will unraid be smart enough to divide it up and start a new disk once disk2 is full?

2. If the former happens and the torrent fails, how do I try again without having this limitation?

[JorgeB]

Unraid never moves files between disks, so if it gets full the download will fail.

 

You'd need to manually move some files to a different disk (same folder) then re-start the torrent

 

 

[sanfark]

But what is the point of "High Water Table > Automatically split any directory as required'? I thought that meant unraid will figure out the data allocation

[trurl]

It decides in advance where to put a file before it starts writing it, and in the general case, it has no way to know how large the file will become. This is the point of the Minimum Free setting

[itimpi]

9 minutes ago, sannitig said:

But what is the point of "High Water Table > Automatically split any directory as required'? I thought that meant unraid will figure out the data allocation

It does - at the point the file is first opened and has 0 size.  If the free space is below Minimum Free Space at that point another drive is chosen.    Once the drive is chosen Unraid does not change its mind if the file subsequently does not fit - it gives an out of space error.   That is why you want have to have a value for minimum free space  that is larger than the biggest new file that might be written to the disk.   

[JorgeB]

14 hours ago, JorgeB said:

If the files were preallocated

I meant the reverse, the files are likely getting all created but not prealocated, most torrent clients have a preallocation option, that should help with a case like this.