tree 7c28b2fec8833eafa47c714b8f007b6a6fe1fed5
parent b02b83c63e16e288ff98dc3992fa26dda25da35f
author QUICHE team <quiche-dev@google.com> 1767777726 -0800
committer Copybara-Service <copybara-worker@google.com> 1767777778 -0800

Fix gap filling ACK logic in QuicReceivedPacketManager.

Updates the logic for sending immediate ACKs when receiving out-of-order packets. Previously, any packet smaller than last_sent_largest_acked_ would trigger an immediate ACK, regardless of the threshold.

This CL ensures compliance with draft-ietf-quic-ack-frequency-13 Section 6.2 by respecting the reordering_threshold: immediate ACKs are now only triggered if the received packet is outside the reordering window (i.e., less than or equal to last_sent_largest_acked_ - reordering_threshold_).

This reduces the number of immediate ACKs sent on networks with packet reordering, improving efficiency.

Handles underflow scenarios: if last_sent_largest_acked_ is smaller than the reordering_threshold_, no immediate ACK is sent, preventing incorrect immediate ACKs when the reordering threshold exceeds the largest acked packet.

Protected by default disabled --quic_reloadable_flag_quic_fix_gap_filling_ack_logic.

PiperOrigin-RevId: 853138944