- [OPTIMIZATION] Merge series of ACKs if possible
Parsed single-range ACK frames (that is the majority of frames) are
saved in the connection and their processing is deferred until the
connection is ticked. If several ACKs come in a series between
adjacent ticks, we check whether the latest ACK is a strict superset
of the saved ACK. If it is, the older ACK is not processed.
If ACK frames can be merged, they are merged and only one of them is
either processed or saved.
- [OPTIMIZATION] Speed up ACK verification by simplifying send history.
Never generate a gap in the sent packet number sequence. This reduces
the send history to a single number instead of potentially a series of
packet ranges and thereby speeds up ACK verification.
By default, detecting a gap in the send history is not fatal: only a
single warning is generated per connection. The connection can continue
to operate even if the ACK verification code is not able to detect some
inconsistencies.
- [OPTIMIZATION] Rearrange the lsquic_send_ctl struct
The first part of struct lsquic_send_ctl now consists of members that
are used in lsquic_send_ctl_got_ack() (in the absense of packet loss,
which is the normal case). To speed up reads and writes, we no longer
try to save space by using 8- and 16-bit integers. Use regular integer
width for everything.
- [OPTIMIZATION] Cache size of sent packet.
- [OPTIMIZATION] Keep track of the largest ACKed in packet_out
Instead of parsing our own ACK frames when packet has been acked,
use the value saved in the packet_out structure when the ACK frame
was generated.
- [OPTIMIZATION] Take RTT sampling conditional out of ACK loop
- [OPTIMIZATION] ACK processing: only call clock_gettime() if needed
- [OPTIMIZATION] Several code-level optimizations to ACK processing.
- Fix: http_client: fix -I flag; switch assert() to abort()
