Chat-20080513

From Nsnam
Jump to navigation Jump to search
The printable version is no longer supported and may have rendering errors. Please update your browser bookmarks and please use the default browser print function instead.

This is the archive for the IRC chat on 2008/05/13. Full transcript is below, notes follow.

Participating: Florian, Hagen, Joe, Mathieu, Tom

Major discussion points:

  • Liu has been updating the Wiki w/ Quagga notes
  • Hagen has been working through some parallelizations basics, passing packets through sockets
    • Some discussion about synchronizing w/ Craig's emulation work
  • ns-3 demo proposal was submitted to SIGCOMM by Tom
  • Joe posted some basic draft code outlining the statistics framework

Transcript

* Now talking on #ns-3
* Topic for #ns-3 is: gsoc: send questions to ns-developers (http://mailman.isi.edu/mailman/listinfo/ns-developers) if no one answers here
* Topic for #ns-3 set by mathieu_ at Wed Mar 26 12:09:23 2008
* tomh (i=824c2013@gateway/web/ajax/mibbit.com/x-7f5a787b86ea1c6b) has joined #ns-3
<tjkopena> hi all
<tomh> hi joe
<tjkopena> hi tom; george mentioned that he wanted to stop by but is at DARPA today and can't join us (not that we had really discussed an organized chat last week)
<tomh> yes, who else besides hagen is here for the gsoc chat?
<tjkopena> all three are logged in, but I don't know if they're actually here
<lacage> morning
<tjkopena> hi lacage
<hgntmp> as I know fw is finish his master theses these days, not sure if he will join us
<hgntmp> good morning to everyone!
<tjkopena> hi hagen
<tomh> good morning
<tomh> I don't know whether LJ__ is joining, but I can give a brief update
<tomh> LJ__ has been developing his plan on the wiki:  http://www.nsnam.org/wiki/index.php/Real_World_Application_Integration
<tomh> Mathieu suggested on friday for him to get started by looking at how to support netlink sockets via the process API
<tomh> that is independent of working on the regular socket api which is in flux
<tomh> hgntmp, do you have a plan posted like LJ__ has done (on the wiki)?
<tjkopena> LJ__'s wiki page looks good
<hgntmp> btw: i am _familar_ with netlink sockets for linux (I used this as a transport mechanism some days ago)
<tomh> ok, great-- will let him know
<hgntmp> but as already said: netlink is one of the biggest protocols in the stack - not that easy
<hgntmp> right
<tomh> probably we will support, initially, the pieces needed to modify the kernel forwarding table
<hgntmp> recently I looked in the olsrd implementation, they use nowadays netlinks socket for linux to manipulate them
<hgntmp> (maybe a smooth introduction from userspace side)
<fw_> i'm here.
<hgntmp> moin
<fw_> i sent mail to ns-developers that has the current state of the nsc work
<fw_> i suspect that the mail is pending in the moderation queue, it will hopefull hit the list later today
<hgntmp> got it
<lacage> tomh, hgntmp yes, the goal is to start with only the pieces we need for zebra and these should be relatively minimal.
<tomh> it did hit the moderation queue (I have whitelisted your email for the future)
<lacage> hgn, so, what is the status of your work on the parallel stuff ?
<tjkopena> hgntmp, have you & george been able to hookup & chat specifics?
<hgntmp> really similar to the stuff i wrote to you
<hgntmp> currently i stopped because I need additional information how I can convert this packet class
<hgntmp> the current status:
<hgntmp> i start two ns3 processes and both create a socket, one open, bind, listen and accept()
<lacage> hgntmp, if you have specific questions for me, it would be more helpful to send them to the ML if you can
<lacage> i.e., I am about to answer your email but it would be nice if others could see what you are up to.
<hgntmp> the other one connect with the server socket
<hgntmp> lacage: ok
<hgntmp> afterwards I serialize the packet, get a Buffer instance, PeekData() and write() to the socket
<hgntmp> the client, on the other side, read() the data, build a Buffer and afterwards a Packet instance
<lacage> out of curiosity, why are you actually marshalling the packets through a socket ? do you want your parallel implementation to work on distributed machines rather than a single multicore machine ?
<lacage> (for the latter, you would just need some careful locking, obviously)
<hgntmp> lacage: it was the suggestion from george
<lacage> ah, ok.
<hgntmp> I mean it is still ok, the implementation via shared mem and semaphores (or whatever synchronization is used) could be implemented afterwards
<hgntmp> there are some other fundamental challenges in the area of space parallel appraoch
<hgntmp> especially for wireless (calculation interferences et cetera) 
<hgntmp> but I send my proposal to george and we will discuss these challenges in the next couple of days (after the trip)
<lacage> cool
<lacage> tjkopena, I see that you have started on the ns-3-stat branch. are you going to work on that in the next few days ?
<tjkopena> yes
<tjkopena> so there's an ok sketch in there
<tjkopena> I am going to email vincent & the list later today
<tjkopena> this evening I'm going to clean it up a bit, add another simple example (means) and demo hooking to a trace
<tjkopena> hopefully I can get vincent involved & work on it together
<tjkopena> I only need a couple basic things for now, so hopefully he can pick up on some of the more interesting statistics
<tjkopena> I just 1) needed some of this right now and 2) wanted to make sure it was fairly general, and not tied into specific networking metrics
<lacage> tjkopena, ok.
<tjkopena> if you have comments on that branch I'd be happy to hear them
<lacage> fw_, answered you
<fw_> lacage: thanks, will read it asap
<lacage> tjkopena, I will try to look at it carefully today
<tomh> (reposting-- maybe I missed the response)  hgntmp, do you have any plans posted like LJ__ has done (on the wiki)?
<lacage> fw_, btw, were you able to catch up with sam ?
<lacage> fw_, I understand that 8 in the morning is too early for a googler :)
<tjkopena> lacage, sounds good; there are some design notes in docs/ as well
<hgntmp> tomh: of course - I will do today - I swear! ;)
<lacage> tjkopena, yeah, I saw that
<lacage> tjkopena, did you have comments on my stats email from last week ?
<tjkopena> yes, I thought it was a great writeup
<tjkopena> not too sure on the specifics, but the motivations & goals were good, along with the references
<tjkopena> I was going to crib most of it when I turn the design notes into a larger writeup
<lacage> tjkopena, ok. looks like you are going to write the ns-3-stats paper :)
<lacage> tjkopena, btw, did you submit a sigcomm poster ?
<tjkopena> I did not in the end
<tjkopena> tomh, sorry I did not get back to your email about that
<lacage> tjkopena, ok. tom did submit a demo/poster proposal.
<tomh> hgntmp, once your work starts to get posted, I've asked Craig Dowell to track it as well, since he is working on real-time scheduler and emulation, and is working some multicore issues there too
<lacage> tomh, I replied your last email about sockets
<tomh> it would be nice to harmonize craig's emulation work with your work
<tjkopena> lacage, I saw that.  I may still come out (have to determine that yet), in which case I'd be happy to help w/ the demo & could bring machines (tablets), etc
<tomh> tjkopena, yes I submitted a demo proposal-- did you?
<tomh> I'll send a copy later
<tjkopena> no
<lacage> tjkopena, ok. sounds great.
<tjkopena> but am still thinking about coming out for it
<tjkopena> also, tom (I mentioned this to lacage earlier), I'm coming out to Seattle just before the 4th of July and would be interested in getting together if people have time
<tjkopena> I'm buying air tickets to night & will email everyone
<tomh> great, it is a nice time around here to visit
<lacage> tomh, the beginning of summer :)
<lacage> I am still waiting for it...
<tomh> lacage, we have two more days of winter then you should be happier
<lacage> yeah, I saw the WE forecast
<tomh> lacage, I added a SocketsDefault class last night
<tomh> if you think there is a cleaner approach, we can look at it
<fw_> lacage: yeah
<fw_> lacage: already talked to him about nsc integration stuff.
<lacage> tomh, as I replied, I think that attributes would work.
<hgntmp> I must leave now - for additional info regarding my person I will read the IRC backlog afterwards
<lacage> hgntmp, ok. have a good night
<hgntmp> or email! ;)
<hgntmp> 5:46pm
<lacage> fw_, were you able to setup a regular meeting ? or is this just a couple of emails ?
<fw_> emails and jabber
* hgntmp (i=50f62021@gateway/web/ajax/mibbit.com/x-94ba2ca630b3953c) has left #ns-3
<fw_> at the moment i send him a weekly status report
<tomh> lacage, well, I am not going to hold up my post to ns-developers for that (which I'm trying to write in parallel to this chat)
<lacage> fw_, ok. if you can and if he is ok with it, it might make sense to send it to ns-dev.
<lacage> tomh, certainly. I will comment on the list.
<tomh> I have not pulled the raw buffer variants.   That will still be controversial despite what we discussed on Friday.  I would prefer to let it lie.
<lacage> what does "let it lie" means ?
<lacage> does it mean that you do not want to do it _now_ ? or that you do not want to do it _ever_ ?
* lacage is curious
<tomh> not reopen the issue
<tomh> I will comment it on the list
<lacage> ok
<lacage> thanks
<tjkopena> ok guys, have to run; will chat later.  thx
* Disconnected ().