[jacorb-developer] Delay in serial communication

[Kujtim Hyseni]

Hello Nick, 

Ok, I will do what you have suggested. But, I have some questions regarding the process...

*) Will someone of JacORB team contact me later when they begin to test my code
*) You probably don't have 8051 microcontroller at back-end (to receive response from), but you will need to "simulate" it, thus, you will need "another" PC which communicates with PC hosting the JacORB server I am submitting. The "other" PC will listen at sepcified port and respond sime message which syntax is: first byte=length, other bytes of length-1 any contect. Probbaly I will need to supply you with the code of "other" PC
*) But first, please do more simple test - a simple server, with an interface with just one method with no parameters which returns void but implements  Thread.sleep(5000); instruction and see how it affects your PC. In Windows: please start media player or see how your whole operating system is blocked.

Anyway, I am available to you at any time ... so please contact me if I need you.

Kujtim

> Date: Thu, 26 Jul 2012 11:05:21 +0100
> From: jacorb at goots.org
> To: jacorb-developer at lists.spline.inf.fu-berlin.de
> CC: kujtimhyseni at hotmail.com
> Subject: Re: [jacorb-developer] Delay in serial communication
> 
> 
> Checking back through my emails I find I did reply and you did not enter 
> a ticket with a standalone compilable test case to demonstrate the 
> issue. I have repeated my email below:
> 
> 
> > On 19/04/12 08:54, Kujtim Hyseni wrote:
> > - show quoted text -
> >
> > You have still not provided your IDL/Client code (and in fact a complete CORBA application would be useful). See below for how to submit it.
> >
> >> The solutions outside of the 'CORBA
> >> world' is very similar and is present as follows:
> >
> > <snipped code>
> >
> > - show quoted text -
> >
> >
> > Any communication 'over the wire' will cause *some* delay comparing to a direct local call (TCP transfer/marshalling etc). You have mentioned JacORB 'causes a delay' but have not shown that the simple overhead of a remote CORBA call is causing the supposed delays.
> >
> > Presumely in your CORBA application the client is calling operation1/2? How does your Thread end? I can't see any code to end it?
> >
> > You also mention that the application is causing a load on the CPU. Have you tried profiling it to see where the issue is?
> >
> > If you can demonstrate a bug in JacORB then please submit a standalone compilable test case showing the problem by submitting a bugzilla here
> > http://www.jacorb.org/contrib.html
> >
> >>  >>Have you tried using Wireshark to analyse the network trace?
> >> I cannot use Wireshark in local (localhost) invocations since Windows
> >> (XP in my case) doesn't allows it - I will try it when I will establish
> >> a network.
> >
> > Install Linux in a VM and test using that. Or look at the alternatives here http://wiki.wireshark.org/CaptureSetup/Loopback
> >
> >>  >>Have you
> >>  >>tried turning on JacORB debug logging?
> >> Can you explain how to do this, please?
> >
> > See the JacORB programming guide.
> 
> 
> 
> Regards
> 
> Nick
> 
> 
> 
> 
> On 26/07/12 10:53, Kujtim Hyseni wrote:
> >
> > On date 29 March 2012 I posted the following message at JacORB
> > mailing list:
> >
> > "Hello,
> >
> > for my project I heave developed a class (implementation class) which
> > forwards requests (operations) from client to serial port, waits for
> > response, receives the response and sends it back to client but it
> > takes a long time to perform it. It delays in receiving the response
> > from serial port. For communication with serial port I have developed
> > a dedicated class which implements Runnable and
> > SerialPortEventListener classes. My class communicates serially with
> > 8051 microcontroller. Again, it seems that class delays in receiving
> > the byte stream from microcontroller. Microcontroller has a built in
> > serial port while my PC uses USB-to-Serial cable. When I communicate
> > microcontroller with the class from usual Java program (from main()
> > routine) it works fine and it takes less than a second to receive the
> > response back.
> >
> > I did some measurements (100 requests) in two ways. In the first,
> > communication class is external and is instantiated from
> > implementation class. In the second, communication class is merged
> > with implementation class. The results are: for first way average
> > response time 9.33266 seconds, minimal response time 4.984 seconds
> > while maximal response time 18.015 seconds; for second way average
> > response time 8.62625 seconds, minimal response time 4.969 seconds
> > while maximal response time 16.015 seconds. These values are
> > unacceptable for real time applications and raise the question for
> > using JacORB further.
> >
> >
> > What do you think and suggest about?"
> >
> > Then I got various suggestions (from Nick Cross) such: to install
> > JacORB 3.0 and provide the code samples.
> >
> > I now installed JacORB 3.0 and made the same tests, but, received the
> > same delays - just to illustrate for 5 requests times are (in
> > seconds): 6.735, 12, 8, 7 and 13. When I invoke the requests from
> > usual java program it takes less than a second per request - this is
> > normal since routines at this phase are void , they just return
> > values.
> >
> > Again, these delays are unacceptable for out application and if not
> > resolved we will abandon JacORB and move to another ORB or perhaps
> > Web service technology.
> >
> > Can someone from JacORB developers or mailing list contributors pay
> > some attention and help resolving this issue, in order to continue
> > with my project and use JacORB.
> >
> > Kujtim Hyseni  _______________________________________________
> > jacorb-developer maillist  -
> > jacorb-developer at lists.spline.inf.fu-berlin.de
> > https://lists.spline.inf.fu-berlin.de/mailman/listinfo/jacorb-developer
> >