Question about storage limitations with unRAID 6

[Noob]

I've had two failures during my current evaluation/trial period that both seem odd to me. Perhaps someone more familiar can explain how the storage limits work in unRAID.

 

First, my array had 400GB of space left in it and I attempted to copy 150GB to it using Windows File Explorer. I got an error stating that I was 80GB short to complete the transfer. That roughly corresponded to the minimum free space setting I configured for the share earlier. I went back to the settings page for the share, made minimum free space zero, and tried to copy a second time. Same error: 80GB short for a 150GB copy. I have 400GB free. What gives?

 

Second, I'm running the Unbalance plugin to clear a drive with 900GB on it in order to assign that drive my second parity disk after it's empty. I added two 500GB disks to the array, precleared and formatted them, and they had over 900GB of free space collectively. Using unbalance, I selected the 900GB drive as the "From" drive, and left all of the other drives checked as "To" drives. Unbalance gave me an error stating that I didn't have enough space available to clear the 900GB of data off my drive. Lies! I had about 250GB on the array before I added the two 500GB drives. I have more space than I need for this transfer.

 

What gives? Why am I getting so many weird and blatantly wrong free space errors with unRAID?

[John_M]

You need to post your diagnostics, otherwise you'll only get guesses for replies. Here's mine: check your split levels.

 

[Noob]

You need to post your diagnostics, otherwise you'll only get guesses for replies. Here's mine: check your split levels.

 

First, I don't know how to post my diagnostics. More detail would be great.

 

Second, my split level for all shares is set to "Automatically split any directory as required," so I don't believe that to be the cause.

[ashman70]

Go to the tools menu then to diagnostics, it will download your diagnostics and then you attach that to your next post in this thread.

[SSD]

UnRaid needs to store each file on a single disk. It will use your share configuration to decide what that disk is. It had no idea (or doesn't care) how big the file you are trying to copy is. If the file fits on the rest of that disk, great. If it doesn't, you've run out of space. It won't split a file across two disks.

 

So an example, you have min free space set to 100G and set for fill up disk method. You have two disks in the share, the first had 101G free, the second has 8T free. You try to copy a 200G file. It picks the first disk because you are using fill up and there is more than 100G available. You will run out of space.

 

Another example, you have split level set to one and are copying a file to an existing second level directory. You are using most free method. The disk containing the second level folder only has 2M remaining. But anther disk in the share had 3T remaining. The file is going to use the split level and select to copy the file to the disk with 2M free . And unless it is pretty small, the copy will fail.

 

Hope this explains why all the questions about your method and split level. We believe that it's the source of your issue. That or a misguided notion unRaid spits or stripes data.

[Noob]

Thank you all for your helpful replies. To be clear, I understand that unRAID doesn't stripe data. My minimum free space settings are set above what I need by quite a lot and, even considering that, I have space left, but unRAID will not allow me to store data to the disk. My split settings are as generous as the GUI will allow me to configure them to be.

 

I found the log for unBalance, which I think is a helpful addition to the diagnostics. I've included a helpful execpt from unBalance, indicating that each drive has reserved free space of 450000000 (is that 45GB?), which doesn't correspond to any of my share settings.

 

Any help is greatly appreciated.

unBalance_Log.txt

diagnostics-20170215-0053.zip

[S80_UK]

I found the log for unBalance, which I think is a helpful addition to the diagnostics. I've included a helpful execpt from unBalance, indicating that each drive has reserved free space of 450000000 (is that 45GB?), which doesn't correspond to any of my share settings.

 

Any help is greatly appreciated.

I'm pretty sure that 450000000 (as in your unBalance log) is 450GB, not 45GB.  That could be the problem.

[Noob]

I never configured that setting, so that must have been the default that came with the plugin. Any idea how to adjust it?

 

EDIT: I found it with only a cursory amount of searching. See screenshot. It's 450MB, so that should not be creating this failure.

 

What's next? Anyone have additional suggestions?

[Noob]

Bingo!

 

I think I've sorted out this problem. The folder that is causing unBalance to generate an error is 506GB, whereas my largest target disk is only 500GB. It looks like unBalance doesn't want to split the folder to fit on two drives, so I need any single drive to have at least 506GB of space in order to make the move. I'm going to manually shuffle a few files off of that drive and onto another and I expect unBalance will move right along after that.

 

Thank you all for the suggestions Live and learn!

[S80_UK]

Well done.  Sorry for the mistake on the free space number - I was thinking about the unRAID minimum free space which is expressed in kilobytes rather than bytes.

 

Glad you found the problem. 

[Noob]

So, I'm back again guys. Unbalance worked itself out after I manually rearranged some files, but I still can't copy anything large to my array.

 

I have 700GB free with minimum free space set to 40GB. When I try to copy over 140GB unRAID gives me an error saying I'm short 80GB (same error as in my initial post).

 

What causes this? How can I try to resolve it? Having an array that won't accept data is wearing on me :-/

[gubbgnutten]

Updated diagnostics to reflect the current situation would be great. 700GB free is not really interesting, we need to know the free space of the individual drives contributing to the 700.

 

Which share are you copying the file to? Where do you actually see the error? What's the exact wording? Do you get the error immediately or halfway through the transfer? Is the "over 140GB" a single file?

 

BTW, you should set the minimum free space to a value larger than the largest file you are going to write to the user share. unRAID does not know how large a new file will be. With minimum free set too low, it can try to write to a disk with too little space free.

[Noob]

Very little has changed since I posted my last diagnositc, other than shuffling some drives around. New data is attached.

 

In order, the answers to your questions are:

 

1) There are six data disks in the array. Free space is as follows: 31GB, 125GB, 71GB, 186GB, 7GB, 250GB. Total free space is nearly 700GB.

 

2) I'm copying to the Media share which is set to include all drives. The error pops up in Windows File Explorer when I try to drag & drop my new data onto the share. See attached error message screenshot. It is immediate, the transfer doesn't even begin. The 140GB is split over roughly 20 files.

 

3) Yes, I understand how minimum free space works. I don't anticipate moving any files to the media share that are over 40GB at this time. If I do in the future, I will update the setting accordingly.

 

Thanks for your help.

[JonathanM]

Very little has changed since I posted my last diagnositc, other than shuffling some drives around. New data is attached.

Try changing the split level for that share to "Automatically split any directory as required". If it's already set that way, set it to something else and apply it, then set it back and apply it.

[Noob]

It was already set that way, but I changed it, applied the change, and set it back. Still getting the same error.

[gubbgnutten]

And exactly how much space is Explorer telling you is available on the Movies share?

[Noob]

It doesn't report free space because the share isn't mounted, it's mapped.

 

See screenshot of "My Computer" for reference.

[Noob]

I mounted it so I could answer your question. Explorer shows Media to have 160GB free, which differs from the free space being reported in the unRAID GUI.

Edited February 21, 2017 by Noob