Question about pf.conf queues

Hello,

I have a question regarding queuing and priorities in pf.conf on OpenBSD
7.2.

I have a basic gateway configuration - a PC with two NIC's (em0, em1).
One interface is connected to the LAN and one interface is connected to
the Internet with a public IP and with a bandwidth of approximately 60
Mbps down and 10 Mbps up. I perform NAT on the gateway.

In terms of queuing, I'd like to make use of the following:

** Queue using HFSC for all outbound traffic

** Flow manager for the queue for fair queue utilization

** For TCP traffic I would like to use two priorities - one for TCP data
packets and one for TCP ACKs (as mentioned in Peter Hansteen's "Book of
pf 3rd edition" in chapter 7)

Current configuration pf.conf:


ext_if = "em0"
int_if = "em1"

set skip on lo0

queue rootq on $ext_if bandwidth 55M max 55M
queue dataq parent rootq bandwidth 55M max 55M flows 1024 \
qlimit 1024 default

match out on $ext_if inet from ($int_if:network) to any nat-to ($ext_if:0)

block all

match in on $int_if inet tag LAN
match out on $ext_if inet queue dataq set prio (5, 6) tag INTERNET

pass in quick on $int_if tagged LAN
pass out quick on $ext_if tagged INTERNET


My question are:

1. For better utilization of TCP traffic I have two priorities assigned
to the queue. Do I require more than one sub queue for this to work ?
I don't intend to subdivide my traffic up (i.e. a SSH queue, and HTTP/S
queue, etc.), I just want all my TCP traffic to benefit from better
utilization with the two priorities.

2. If this configuration is currently correct, are they any other
changes I should make for better queuing (ie: better bandwidth
utilization) ?

3. Given the importance of time keeping, would it be a good idea to have
another queue for NTP traffic and use the highest priority of 7 for it ?

Thanks,

- J