Queue monitoring syntax!
Thu, 15 Oct 1998 15:21:37 -0700
I've been tinkering with the flow monitors and use code like this.
# set the links and create a flow monitor
# r1 ---> r2
set slink [$ns link $nodes(r1) $nodes(r2) ]
set fm [open all.fm w]
set fmon [$ns makeflowmon Fid ]
$ns attach-fmon $slink $fmon
$fmon attach $fm
$ns at $finishTime "$fmon dump"
The last command dumps the aggregate stats (bytes, packets, arrivals, drops)
etc.to the file all.fm when my simulation ends. Checkout the file
'flowmon.cc' for the output format as it differs from the documentation.
Check out ns/tcl/test/test-suite-simple for other examples.
Now that I've said that I discovered that the flow monitor can affect the
flow stats if I call $fmon dump during the simulation. So I only call it at
the end and I count packets in the trace file to get intermediate stats.
As far as plots, I haven't figured out how to get the results into xgraph so
I'm just using Excel :-(
Hope this helps.
> From: Farhan Shallwani[SMTP:Farhan.Shallwani.firstname.lastname@example.org]
> Sent: Thursday, October 15, 1998 7:05 AM
> To: 'email@example.com'
> Subject: Queue monitoring syntax!
> Hi guys!
> Really need help for the following; even if u dont know the answers to all
> of them, partial answers would be fine with me. Thanks!
> How to trace the following variables at a gateway:
> * Packet drops
> * Packet queued
> * Total # of packets sent (Integration)
> * Total # of packets dropped
> * Queue size (instantaneous and average)
> A "monitor-queue" object is required to access the above
> variables; how to manipulate that object, link it to a gateway, the
> syntax is needed.
> How to write the above values to a graph file
> (graphfile.xg), such that it is compatible to xgraph; i.e. "xgraph
> graphfile.xg" plots the graph.
> Also needed is the correct syntax for: "per-flow monitoring"
> and "integrator objects".