Solved TODO "log PNs being ACKed too late"?

[HektikR]

I've noticed this TODO comment, which was introduced in 2020.

quicly/lib/quicly.c

Line 6066 in 9dc56ed

/* TODO log PNs being ACKed too late */

I'm wondering whether the TODO is already solved by this line (from 2022):

quicly/lib/quicly.c

Line 6116 in 9dc56ed

PTLS_LOG_ELEMENT_BOOL(is_late_ack, is_late_ack);

[kazuho]

Maybe those "too late" and those that were "late" are different.

IIRC, the TODO is pointing out that we might want to have a way of observing packets newly acked after they have been retired from the sentmap, when init_acks_iter is called right above.

I'm not sure if that's directly possible, though it might make sense to log when the minimal PN kept in the sentmap is updated to a larger value.