[ns] IFQ and RTR queue /drops
Khoa A To
takhoa at rice.edu
Fri Feb 6 07:44:59 PST 2004
I believe that "RTR" specifies that the drop was initiated by the routing
protocol whereas "IFQ" specifies that the drop was initiated by the queue.
I don't know if there is a difference between a routing queue vs. a lower
The column next to that is the reason for the drop. In that column,
sometimes, you see "IFQ" or "TOUT", etc. Those are reasons for the drop.
For those, you can find them in trace/cmu-trace.h
Hope that helps.
On Fri, 6 Feb 2004, [iso-8859-1] ns user wrote:
> Thanks a lot.
> Could you give some pointers where I can learn more
> 1. RTR queuing and drops. -
> 2. IFQ queuing and drops
> 3. difference between them ?
> Or if anyone knew, please write couple of lines.
> --- Padmaparna Haldar <haldar at ISI.EDU> wrote: >
> > Did you look at ~ns/trace/cmu-trace.h ? Thats the
> > place where all drop
> > types are explained. You'll see two types of IFQ
> > drops (and this probably
> > should be changed to different acronyms to remove
> > confusion), one for RTR
> > queue full and the other for IFQ full. This kind of
> > matches with the trace
> > level you see (RTR or IFQ in this ex) in the traces.
> > --Padma
> > On Thu, 5 Feb 2004, ns user wrote:
> > Hi all,
> > In new trace format, Nl is for trace level, and Nw
> > is for reason for
> > event.
> > In my trace files, I get many drop packets, of which
> > some with 'Nw' reason
> > as IFQ and sometimes 'Nl' as IFQ.
> > See two examples that I have given.
> > First:
> > d -t 35.953355387 -Hs 3 -Hd 5 -Ni 3 -Nx 47.97 -Ny
> > 594.53 -Nz 0.00 -Ne
> > 95.229983 -Nl IFQ -Nw --- -Ma 13a -Md
> > 5 -Ms 3 -Mt 800 -Is 8.0 -Id 1.0 -It cbr -Il 532 -If
> > 0 -Ii 4659 -Iv 29 -Pn
> > cbr -Pi 1366 -Pf 1 -Po 4
> > Second:
> > d -t 45.841054455 -Hs 6 -Hd -2 -Ni 6 -Nx 575.11 -Ny
> > 279.90 -Nz 0.00 -Ne
> > 93.091232 -Nl RTR -Nw IFQ -Ma 0 -Md
> > 0 -Ms 0 -Mt 0 -Is 6.0 -Id 3.0 -It cbr -Il 532 -If 0
> > -Ii 6585 -Iv 30 -Pn
> > cbr -Pi 966 -Pf 0 -Po 5
> > In first, trace level is IFQ. How is trace level is
> > IFQ ? What does it
> > mean ?
> > And no reason Nw ....?
> > In second, trace level is RTR and reason for drop is
> > IFQ.
> > I do not understand this part especially, both are
> > drop cbr packets but
> > what is the difference between IFQ
> > in Nl and Nw (level and reason)
> > Manual doesnt supply sufficient detail. Please
> > reply
> > Cheers
> > Siva
> > >
> > >
> > --
> > ------------------------------------------------
> > Be true to your work, your word, and your friend.
> > --Thoreau
> > Padmaparna Haldar
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