queue tree - queue type in parent vs child

RouterOS General
1

I have a queue tree with parent node (to limit overall rate) and child nodes (packet marked packets)
I need some clarification about ‘queue type’ setting in parent and child nodes.

If I set qtype=pcq in child nodes, should I set the qtype=pcq in parent as well ?
The way I understand is that parent node is only use to ensure that total rate from child nodes does not exceed the specified rate.
Does qtype in the parent actually is used by ROS ?

e.g,
child qtype=pcq, parent qtype=fifo // assume parent qtype dont matter, streams are classified in child
child qtype=fifo, parent qtype=pcq // classify streams in parent, dont classify streams in child
child qtype=pcq, parent qtype=pcq // classify streams in parent and in child ???

can someone please clarify how this works in ROS ?

cheers

2

from my readings all these years i have conclude that parent queue type does not matter what is set to. only child queues type matter.
parent queue helps to apply max limits of your internet connection.