Duplicati filling local disk for cloud backup?


I’m having a weird situation that I cannot understand.

I am trying to make a backup of my local computer hard drive to my OneDrive account (when I click on “test connection” in the settings dialog, things appear to be working well). This is the first backup I am running. 200GB have been uploaded according to Duplicati’s web interface, and here are the two things I am noticing:

My local hard drive capacity has fallen by 200GB
My onedrive account is still empty and shows no sign of Duplicati uploading any files to it

This leads me to believe that Duplicati is copying my drive files to the same drive (perhaps before uploading it in zip format?). However I did not anticipate this behavior and my drive does not have double capacity, so I cannot finish the first backup. Unfortunately I cannot validate my assumption because I cannot find where Duplicati is copying my files to.

Could someone please explain to me what is happening exactly and how can I solve this problem?
Thank you very much!

Hi, @theUmbra - welcome to the forum!

Historically a high disk usage like you’re reporting has been tied to an overly large dblock (“upload volume size”) size and/or --asynchronous-upload-limit value. Are you using any custom parameters or just going with the defaults?

Ah yes, I am using a very large upload volume size. Thank you. I thought this meant the size on the cloud service that I was willing to allocate. I understand what it means now. I will change it. However, how can I make sure that all previous “dblocks” are deleted from my computer (ie where are they stored?)

Yes… this happened to me too. Perhaps, description of ‘upload volume size’ should be improved.

I think this was discussed a bit here:

Depending on how you’re running Duplicati (tray icon, service, portable-mode, etc.) it could be in:

  • %temp%
  • %tmp% (often the same as %temp%)
  • %systemroot%/temp
  • wherever you set the --temp-dir to (if you’re using that advanced parameter)

If you’re not finding the expected files in any of those places, while it’s not elegant, a global drive search for Duplicati-* might point you in the right direction. Otherwise, a disk usage tool like WinDirStat or similar might also help you find your “very large upload volume size” sized files. :slight_smile: