GRED on queue or pipe

[Jon Otterholm]

Doing some test of gred in dummynet. My ruleset consists of a number of 
queues connected to the same pipe. Queues have different weight and I 
want to make use of gred instead of taildrop.

Should i define gred on the queues or on the pipe? To me it seems 
reasonable to set it on the pipe and let the pipe handle the weight from 
the queues.

How do I define the queue-depth on queues and pipes? If the pipe has 
2000 slots should queues have the same number on queues or should the 
total number of slots in all queues sum up to the number defined in the 
pipe?

Example:

ipfw queue 1000 config pipe 1000 weight 5
ipfw queue 2000 config pipe 2000 weight 5
ipfw queue 1001 config pipe 1000 weight 80
ipfw queue 2001 config pipe 2000 weight 80
ipfw pipe 1000 config bw 100Mbit/s buckets 65535 queue 2000 gred 
0.002/1800/2000/0.1
ipfw pipe 2000 config bw 100Mbit/s buckets 65535 queue 2000 gred 
0.002/1800/2000/0.1

ipfw add 10 queue 1000 ip from any to table(10) dst-port 25 out xmit em1  
ipfw add 10 queue 2000 ip from table(10) to any dst-port 25 out xmit em0
ipfw add 20 queue 1001 ip from any to table(20) out xmit em1     
ipfw add 20 queue 2001 ip from table(20) to any out xmit em0

//JO