Well, one part of it is that Flatpak pulls data over the network, and sometimes data sent over a network doesn’t arrive in the exact same shape as when it left the original system, which results in that same data being sent in multiple copies - until one manages to arrive correctly.
I think this is actually very unlikely, flatpak is most likely using some TCP based protocol and TCP would take care of this transparently, flatpak wouldn’t know if any packets had to be retransmitted.
Hence why Fedora Linux actually recently removed delta updates for DNF. Turns out it used more data in retries than just downloading a whole package again.
Well, one part of it is that Flatpak pulls data over the network, and sometimes data sent over a network doesn’t arrive in the exact same shape as when it left the original system, which results in that same data being sent in multiple copies - until one manages to arrive correctly.
This sounds the most likely, most apps just hide retries, flatpak shows exact data transfered.
I think this is actually very unlikely, flatpak is most likely using some TCP based protocol and TCP would take care of this transparently, flatpak wouldn’t know if any packets had to be retransmitted.
Could also be that the HTTP server lied about the content length.
It’s a protocol violation to do that, not least because it precludes connection reuse
Hence why Fedora Linux actually recently removed delta updates for DNF. Turns out it used more data in retries than just downloading a whole package again.
Interesting, didnt know that! That sounds like a fixable issue though…
I think they have moved from trying to fix it in DNF, to using the capabilities found in BTRFS for Copy on write. Can’t quite remember exactly.
??? Retransmitted packets don’t get counted towards downloaded file size