We saw this limitation in our app - and it turned out to be the windows handles limitation on the server.

Turning off windows handles in the pb.ini made a miraculous difference - we now run 32-64 separate parallel task at high speed utilizing nearly 100% of compuing resources.

Also make sure your server is configure for maximum compute performance - turn off fair share , etc.

Hi Boris;

  You can also try creating a PB App EXE instance per processor using the SetProcessAffinityMask API.

   I created a system for Passport Canada using the above API with two PB App's. I used 16 instances of App1 that were each bound to one of the 16 cores on one server.The 2nd PB App2 was used as a coordinator App for the 16 App1 instances on each server. Each App1 took it's direction from App2. App2 monitored each App1's work queue, work status, error / restart and coordinated it's normal shutdown.

   I had three servers - thus 16 x 3 = 48 core instances of the PB App1 running. With three App2 coordinator instances. Each App2 communicated with each other - so each App2' knew the overall processing state of all three servers.

   Here are a few presentations that I gave on this architecture / design app;roach at various PB Conferences. This design allowed Passport to process (OCR, locate, redact, update Blob based images in an ASE DBMS at the rate on 1 million per hour!!!!

FYI...

https://sourceforge.net/projects/stdfndclass/files/Presentations/Multi-Threading

https://sourceforge.net/projects/stdfndclass/files/Presentations/OCR

Food for thought!  HTH

Regards ... Chris

The SetProcessAffinityMask Windows API function can be used to assign your app to a specific CPU.

The second argument is a bit mask so set it like this:

mask = 2 ^cpu

Windows declaration:

BOOL SetProcessAffinityMask( [in] HANDLE hProcess, [in] DWORD_PTR dwProcessAffinityMask );

kernel32.dll

In PowerBuilder use Longptr for both arguments.

Hi,

All good advice, but it still doesn't explain why power builder application shows very poor perfomance on multi-core processors, while it may work several times faster on one-core processor

Maybe it's because a single core of the multi-core processor is slower than the tested single core processor?

regards

Hi.

There is no an easy way to do that. It's possible to make your application use multithreading. Not all parts of your application could work in this mode. This mode is suited for background process that can be split somehow to work in different threads.

There is a great article by John Fauss about multithreading and PowerBuilder: Free My GUI! - Multi-Threading in PowerBuilder - Appeon Community. It explains all the basics about this topic, but you are supposed to understand some more advanced topics of pb. I would suggest to read it, and then maybe do some experiments.

Some important points - limitations:

• Multithreading doesn't support visual controls - objects. Even messagebox cannot be used.
• Global variable may be used, but in sharedobjects they are considered as local. This affects also sqlca e.t.c.

You may conclude that any repeated process running inside a transaction cannot be a candidate to be split in a multithread processing. But a process that repeats a specific task n times, and doesn't run in a transaction, it can be a candidate to be executed using sharedobjects.

So, in your case, you will have to:

• Check if you have long running processes that could run in separate threads.
• You will have somehow to decide how many threads to support. This may vary depending on processor and available memory.
• You would have use a controller object (you have to design & built it) to manage your threads.
• You also need an object that will "establish - maintain" communication between your applications and n threads working.

Finally, it's not easy to implement. Depending on your experience in PowerBuilder and the way your application was initially designed it might be less or more work.

Andreas.

PB applications are single threaded applications. So it uses only one core to run.

But you can use SharedObjects to make your application multithreaded. It's not easy to do this.

Here you can find an example: https://community.appeon.com/index.php/codeexchange/powerbuilder/307-a-multi-threaded-data-retrieval-example