[Mini-NDN] Problems measuring elapsed time in MiniNDN experiment

[Saurab Dulal (sdulal)]

Hi André,

The most obvious problem I can think of (as Junxiao explained) is that the data might have been served from the local nfd's cache. Please enable the nfd-logs, look at the consumer's log, and see if local nfd is sending back the cached data.

To set debug nfd log from the experiment: "AppManager(self.ndn, self.ndn.net.hosts, Nfd, logLevel='DEBUG')"

Regarding the resource, you can refer to the Mini-NDN website: http://minindn.memphis.edu/, and also, you can look at some of the examples here: https://github.com/named-data/mini-ndn/tree/master/examples.

If you have any specific questions regarding the setup, please let me know.

Regards,
Saurab Dulal
________________________________
From: André D. Carneiro <adcarneiro at inf.ufrgs.br>
Sent: Wednesday, September 9, 2020 3:02 PM
To: Saurab Dulal (sdulal) <sdulal at memphis.edu>
Subject: RE: [Mini-NDN] Problems measuring elapsed time in MiniNDN experiment


Hi Saurab,



I`m computing m_sTimeDiff in the run function, but it was previously in the onData function and yielded very similar results. Do you think it could be some issue with the setup? Maybe a misconfiguration for NFD or NLSR?



And an additional question, could you point me to some documentation regarding the setup process for MiniNDN? Most of what I did was running the scripts that download and installed all the packages. Maybe there is something more that I missed.





Thanks for the reponse,

André D. Carneiro



From: Saurab Dulal (sdulal)<mailto:sdulal at memphis.edu>
Sent: 09 September 2020 16:20
To: Anurag Muttur via Mini-NDN<mailto:mini-ndn at lists.cs.ucla.edu>
Subject: Re: [Mini-NDN] Problems measuring elapsed time in MiniNDN experiment



Hi Anurag,



Where are you computing "m_sTimeDiff"? are you computing it inside the callback? if the data is received, "onData" should be called and I assume you are computing it there? If not, you will not get the right value.



Additionally, you can also use NDN_LOG. For every log message, it begins with a Unix timestamp which you can use to compute the time difference (this is what I do most of the time).



Regards,

Saurab Dulal





From: Mini-NDN <mini-ndn-bounces at lists.cs.ucla.edu> on behalf of Lan Wang (lanwang) <lanwang at memphis.edu>
Sent: Tuesday, September 8, 2020 11:37 PM
To: Anurag Muttur via Mini-NDN <mini-ndn at lists.cs.ucla.edu>
Subject: [Mini-NDN] Problems measuring elapsed time in MiniNDN experiment







Begin forwarded message:





The attached message has been automatically discarded.

From: Andre Dexheimer Carneiro <andre.dexheimer at inf.ufrgs.br<mailto:andre.dexheimer at inf.ufrgs.br>>

Subject: Problems measuring elapsed time in MiniNDN experiment

Date: September 8, 2020 at 9:41:38 PM CDT

To: mini-ndn at lists.cs.ucla.edu<mailto:mini-ndn at lists.cs.ucla.edu>


Hi,


I am writing an experiment which instantiates NDN producers and consumers as an attempt to simulate a specific scenario with multiple hosts. However, I can't seem to measure the elapsed time correctly, my code right now is:

-----
  dtBegin   = std::chrono::steady_clock::now();
  m_face.expressInterest(interest, bind(&Consumer::onData, this,   _1, _2),
     bind(&Consumer::onNack, this, _1, _2), bind(&Consumer::onTimeout, this, _1));

  // processEvents will block until the requested data is received or a timeout occurs
  m_face.processEvents();

  dtEnd       = std::chrono::steady_clock::now();
  m_sTimeDiff = std::chrono::duration_cast<std::chrono::microseconds>(dtEnd - dtBegin).count();\
-----

Everything seems to work fine, with nodes receiving and sending data as they should, however the recorded times are usually at around 1000 us, which is completely unrealistic as the links have between 2ms and 1000ms delay in my topology. Could anybody cast some light into how to get this metric correctly?



Thanks in advance.

André Dexheimer Carneiro
Computer Enginnering - UFRGS





-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.lists.cs.ucla.edu/pipermail/mini-ndn/attachments/20200910/f20dd5a5/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0704D799D201460797DD080999D700EC.png
Type: image/png
Size: 144 bytes
Desc: 0704D799D201460797DD080999D700EC.png
URL: <http://www.lists.cs.ucla.edu/pipermail/mini-ndn/attachments/20200910/f20dd5a5/attachment.png>