[jacorb-developer] Delay in serial communication

[Nick Cross]

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
>