Re: BQL + Basic Latency under load results - 100Mbit, GSO/TSO off, pfifo_fast vs SFQ vs QFQ

From: Eric Dumazet <redacted>
Date: Mon, 02 Jan 2012 05:33:31 +0100

[PATCH net-next] sch_sfq: dont put new flow at the end of flows

SFQ enqueue algo puts a new flow _behind_ all pre-existing flows in the
circular list. In fact this is probably an old SFQ implementation bug.

100 Mbits = ~8333 full frames per second, or ~8 frames per ms.

With 50 flows, it means your "new flow" will have to wait 50 packets
being sent before its own packet. Thats the ~6ms.

We certainly can change SFQ to give a priority advantage to new flows,
so that next dequeued packet is taken from a new flow, not an old one.

Reported-by: Dave Taht <redacted>
Signed-off-by: Eric Dumazet <redacted>

Applied, thanks Eric.