pftop queue stats

[Jay Aikat]

The large queue limit is just for testing purposes.  Once I figure out 
this logging of the queue at better granularity, I plan to have more 
realistic queue limits.

These are for experiments I am running in our lab to study network 
traffic characteristics and the effect of that on router queuing - just FYI.

Thanks.

Yuriy Grishin wrote:
> Jay Aikat wrote:
>> Hi,
>>     I am looking for a way to log queue stats at less than 1 second 
>> intervals.
>>
>> On my FreeBSD router, the pf.conf file is configured as follows:
>> > altq on $ext_if1 priq bandwidth 622Mb qlimit 65535 queue { tcp_q1 }
>> > queue tcp_q1 on $ext_if1 qlimit 65535 priq (default)
>>
>> Using pftop, I can get queue lengths per second at best.
>> $ pftop -s 1 -v queue -d 1000 > pftop.out
>>
>> Is there an option in pftop to log stats per millisecond, or even 
>> 100ms?  The -s option above seems to default to 1 second at best.
>>
>> Thanks for any pointers you can give me.
> 
> I suppose that there should be some pre-defined variables in the source 
> code.
> BTW Why do you use an extremely large qlimit?