Hi
So I want to configure double QOS in Simple queue.
I created parent queue name=test target ip address 10.10.1.2 max-limit=512000/512000
Also for prioritization purpose I created child queue for icmp. Parent queue is test.
I marked ICMP packets in Mangle
When I create a child queue after it I have unlimited speed. Why ? 
My configuration
Mangle:
0 chain=prerouting action=mark-connection new-connection-mark=icmp_conn
passthrough=yes protocol=icmp
1 chain=prerouting action=mark-packet new-packet-mark=icmp passthrough=no
connection-mark=icmp_conn
Queue:
0 name=“main” target=10.10.1.2/32 parent=none packet-marks=“”
priority=8/8 queue=default-small/default-small limit-at=0/0
max-limit=256k/512k burst-limit=0/0 burst-threshold=0/0 burst-time=0s/0s
1 name=“icmp” target=10.10.1.2/32 parent=main packet-marks=icmp
priority=1/1 queue=default-small/default-small limit-at=0/0
max-limit=240k/500k burst-limit=0/0 burst-threshold=0/0 burst-time=0s/0s
total-priority=1
Model: CCR1036
v.6.2rc1
Firmware - 3.09