Hi, I’m new to Duplicati but have successful got my 500Gb backup working to an external drive. In the process, I had to consider what block and volume sizes would be best and discovered that one of the defaults seems to have changed.
Volume size remains 50Mb (this is easy to spot as it is shown explicitly in the GUI)
Block size is now 1Mb, up from the 100Kb referenced in the documentation (only apparent when you try to adjust the block size, as it then shows the new default)
Have I understood this correctly? I am running Duplicati - 2.1.0.5_stable_2025-03-04
Yes. The motivation was to process increasingly large backups in a reasonable time, because every block requires a database entry (big database) and slows down SQL.
About → Changelog shows it changed in Canary test 2.0.9.100_canary_2024-05-30, however wider visibility would have been in the later releases, including Stable ones.
Anything marked “Community docs” or at URL https://prev-docs.duplicati.com is older.
Sometimes it’s more detailed (which is good), but sometimes the details are outdated.
That’s great. Thanks for the clarification. Left to my own devices and looking at comments in the forum, I’d have probably gone for 500Kb block size for my 500Gb backup, but based on the new default I went for 1Mb and that seems to have gone smoothly. If anyone is interested, I went for a 150Mb volume size which gave me about 7000 files in my backup directory. With those parameters the 500Gb took 2hrs to a local SSD connected over USB3.