Shaper Wizard: When backlogged, high priority queues get zero bandwidth
Shaper wizard results for basic config:
qOthersLow - LinkShare: 5%, 500ms, 5% < This is a flat curve and redundant., 5% for the first 500ms and then 5% after that.
qOthersHigh - LinkShare: 0b, 200ms, 10% < No traffic allowed until service curve opens up!
qAck - LinkShare: 0b, 100ms, 20% < No ACKs allowed until service curve opens up!
Fix: remove m1 and d service curve values to allow traffic to flow immediately. Advanced users can set service curves if they want/need them. Don't prevent traffic from flowing by default!
#2 Updated by Aaron Berland almost 9 years ago
There is no error message output.
The shaper config functions, but logically is not correct. During congestion, having a service curve start at 0 bandwidth drops packets so the low priority queue gets the bandwidth while the higher priority queues are blocked for a moment. Performance is dramatically reduced for acks and high priority traffic during congestion.
I believe this is why qDefault and qOthersLow can get better performance than the higher priority queues and not allow maximum performance.
#4 Updated by Josh Stompro over 8 years ago
I can confirm this as resolved. The qACK and QOthersHigh get created without the Link Share M1 or D options set now. So qACK and QOthersHigh traffic does not get starved for a certain number of ms when the queue is full.
Tested with Dec 2nd nanobsd snapshot.