On Thu, Jul 21, 2022 at 10:56 PM Neal Cardwell [off-list ref] wrote:

On Thu, Jul 21, 2022 at 4:44 PM Wei Wang [off-list ref] wrote:

quoted

This reverts commit 4a41f453bedfd5e9cd040bad509d9da49feb3e2c.

This to-be-reverted commit was meant to apply a stricter rule for the
stack to enter pingpong mode. However, the condition used to check for
interactive session "before(tp->lsndtime, icsk->icsk_ack.lrcvtime)" is
jiffy based and might be too coarse, which delays the stack entering
pingpong mode.
We revert this patch so that we no longer use the above condition to
determine interactive session, and also reduce pingpong threshold to 1.

Fixes: 4a41f453bedf ("tcp: change pingpong threshold to 3")
Reported-by: LemmyHuang <redacted>
Suggested-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Wei Wang <redacted>

---
v2: added Fixes tag

Acked-by: Neal Cardwell <ncardwell@google.com>

Looks great to me. Thanks, Wei!

Reviewed-by: Eric Dumazet <edumazet@google.com>