pfSense

Using the GUI, the mask options didn't apply to the sched limiter.

from ipfw man:

The SCHED_MASK is used to assign flows to one or more scheduler instances, one for each value of the packet's 5-tuple after applying SCHED_MASK.
As an example, using src ip 0xffffff00 creates one instance for each / 24 destination subnet.

The FLOW_MASK, together with the SCHED_MASK, is used to split packets
into flows.As an example, using src ip 0x000000ff together with the
previous SCHED_MASK makes a flow for each individual source address.
Inturn, flows for each / 24 subnet will be sent to the same scheduler instance.

before patch:

sched 7 config pipe 7 type fq_codel target 5ms interval 100ms quantum 300 limit 20480 flows 65535 noecn

after patch:

sched 7 config pipe 7 mask dst-ip6 /128 dst-ip 0xffffffff type fq_codel target 5ms interval 100ms quantum 300 limit 20480 flows 65535 noecn