Hyperthreading??

[Firdousi Farozan Z]

Hi All,

I have a Java multithreaded application, that makes several JNI calls
(native code written in C++). I use database locks all through the C++
code for synchronization.

With Hyperthreading disabled, I am not seeing any issues with my
application. When I enable hyperthreading, my application hangs after a
while. Analyzing the issue, I could see that JNI calls just hang without
returning, which is causing the application to hang.

Does anyone know of any issues related to Hyperthreading and C++?
Platform is win2k. Since the application is already multithreaded and
works fine in a multiprocessor environment, why should it give issues
only when hyperthreading is enabled?

I googled but could not find any proper information. Please let me know
if you have any thoughts.

Thanks,
Firdousi Farozan

 

[Alf P. Steinbach]

follow-up's to [comp.lang.java.machine

* Firdousi Farozan Z:

I have a Java multithreaded application

<url:
http://bugs.sun.com/bugdatabase/sea...us=&subcategory=&type=&keyword=hyperthreading>

 

[EventHelix.com]

Try running your application on a two processor machine with
hyperthreading disabled.

If you still see the problem, the issue migth be with the concurrency
handling in the application itself.

 

[Rolf Magnus]

Try running your application on a two processor machine with
hyperthreading disabled.

Good idea

 

[Firdousi Farozan Z]

Try running your application on a two processor machine with
hyperthreading disabled.

If you still see the problem, the issue migth be with the concurrency
handling in the application itself.

Thanks for getting back !! I have tried my application in a dual CPU
machine and it runs for days without any issues (I use automation). When
hyperthreading is enabled, the same automation scripts reproduces the
issue in 3-4 hours of usage.