http/2: Large transfers have high overhead in Curl_bufq_len about curl HOT 5 CLOSED

Verified that the throughput for this case is improved by ~60% along with one reduced copy & removal of Curl_bufq_len in the hot path post 8.7.0.

Thanks.

from curl.

The code paths have changed for 8.7.0; this may be obsolete.

from curl.

Probably even more in current master. Would be interesting to know if there is any problems there... @icing have you run your benchmarks recently?

from curl.

The observation fits into the implementation restrictions that I talked about in https://github.com/icing/blog/blob/main/curl-h2-perf-evolution.md

tl;dr

There is no longer a bufq holding the response data, it is written directly to the application callbacks now.

from curl.

@laramiel we believe current git master (8.7.0+ really) to not show those problems.

from curl.