Not enough memory for temp dup-* files in c:...\AppData\Local\Temp\

Hi duplicati users,

yesterday I ran duplicati first time (on a Win 10 home PC).
I want to backup ~1,5TByte of Data to a external 4 TB USB Disc.
Duplicati runs on my C: drive, that has just 600 GB room.
So I gues that caused duplicati to be stopped with “not enough room on disc” error as duplicati seems to write its temp files to c:\Users\myuser\AppData\Local\Temp. (e.g. dup-1dd30f56-bcdf-4e52-a78c-9c0042b743e3)

How can I make duplicati to store its temp files to another local drive?
Will duplicati remove that tem files after each backup ?

Thank you!

600GB should be way more than enough room. Can you list any options you may have adjusted from default settings? Thinking specifically of --dblock-size which defaults to 50MiB. Did you change that or any other settings?

I found and tryed to set the option “tempdir” to a drive that has more space (600GB).

What does duplicati do? Does it write all the data (most of them JPGs at my case) encrypted to tempdir first and than to the target drive?

Duplicati reads your files, breaks them into chunks, and packages them in volumes (default size 50MiB). Once a volume is built it is uploaded. It will do 4 volumes simultaneously by default, so it should only use about 200MiB in the temp dir, regardless of how much data you are backing up.

You are using all default options then?

I got 4 volumes, each 44 GByte - maybe because I chose Remote-volume-size 2 TB??

Yep, that’s definitely your problem. That’s what I was asking about above when I referenced the --dblock-size option which is another name for Remote Volume Size.

The notice under that option has important info:

This option does not relate to your maximum backup or file size, nor does it affect deduplication rates. See this page before you change the remote volume size.

I would leave it at the default of 50MiB unless you are using a back end that is limited on number of files, then maybe increase it somewhat. That link has more info.

that was the solution. My problem was, that the GUI did not describe directly, what this option does , onmly in for beginners not really understandable words, whta it does not do.