Extracting qlog files from Firefox about qvis HOT 2 CLOSED

Hey there @chanh1964,

Seems like my article isn't entirely correct/clear here, I'm sorry about that...

Firefox does not support QLOGDIR, but instead makes its own directory based on the firefox process ID in the Operating System's temporary directory.

For example, on my Windows system, this is where I could find the qlogs after enabling the network.http.http3.enable_qlog pref:

The qlog_ suffix will change depending on your firefox instance. And of course the location will be different on linux/mac. But the qlogs seem to be somewhat usable and are written fast enough (you don't need to close firefox or actively wait for the connections to close or anything).

This is consistent with the code from the original commit adding the qlog preference:
https://hg.mozilla.org/integration/autoland/rev/b53e9a8ffb1f#l4.30

Finally, with regards to HTTP/3, I'm afraid only a few stacks really implement qlog for HTTP/3... it looks like that's not in the Firefox qlogs either; they also only do QUIC. The ones I know about that do H3 logging are Cloudflare's quiche and the Python aioquic library, so maybe you can look into those if that's really what you need (though they also don't log everything)?

If you have any more questions, please let me know!

With best regards,
Robin

from qvis.

Hi @rmarx,

I think you have answered all my questions.
Thank you very much.

Best regards,
Chanh

from qvis.