JOCL | Java bindings for OpenCL | GPU library

I am writing a rather large OpenCL program with lots of function calls. I've been having problems with CL_OUT_OF_RESOURCES errors, but I managed to fix the problem with a simple printf statement. This is the code fragment in question:

I'm using maven to import the jogamp dependencies.

Here is the pom.xml content :

If you are running code that makes calls to a native library in Java, what is the usual way of freeing memory allocated by these libraries when the memory allocation should last for the lifetime of the object? In C++, I would use destructors, but Java never really had those and has them even less now.

The specific case I'm most interested in is JOCL, where I have an object that wraps a compiled OpenCL kernel and all of the arguments thereto that are always the same. Structures representing the compiled kernel and the arguments are all allocated on the library side, and JOCL provides a method clReleaseMemObject that you call to decrement a reference counter indicating when the object should be deleted (note that this is a bit different from directly freeing the memory, but I don't think substantially so in this case).

I presume that if the object is still around when the program terminates, everything is cleaned up by the OS, but I'm not so sure about about objects created in a thread. So:

1. If you want the native memory deallocated when the object is garbage collected, is there a proper place to call the method that releases this memory?

2. If the object is one that will last for the duration of a thread, is there a proper place to make this call, or is this even necessary?

Using Maven build I am getting this error. (both in Maven build and pom.xml file) Missing artifact org.bytedeco.javacpp-presets:artoolkitplus:jar:2.3.1-0.0.1-SNAPSHOT and so on for every dependency.

I tried deleting the org.bytedeco folder from my local .m2 repository, but the error persists.

My pom.xml file is as follows

I am learning myself openCL in Java using the jogamp jocl libraries. One of my tests is ceating a Mandelbrot map. I have four tests: simple serial, parallel using the Java executor interface, openCL for a single device and openCL for multiple devices. The first three are ok, the last one not. When I compare the (correct) output of the multiple device with the incorrect output of the multiple device solution I notice that the colors are about the same but that the output of the last one is garbled. I think I understand where the problem resides but I can't solve it.

The trouble is (imho) in the fact that openCL uses vector buffers and that I have to translate the output into a matrix. I think that this translation is incorrect. I parallize the code by dividing the mandelbrot map into rectangles where the width (xSize) is divided by the number of tasks and the height (ySize) is preserved. I think I am able to transmit that info correct into the kernel, but translating it back is incorrect.

I have been working on programming a convolutional back-propagation neural network recently and I have mainly been using Java to run the program and libGDX for the graphical visualizations. Through heavy research, I have found that to heavily increase performance and efficiency, I should preform the matrix calculations on the graphics card instead of on the CPU.

After looking through sources online, I found that the main way to preform such calculations on the graphics card was through OpenCl. After even more research, I discovered that my main two options for OpenCl support on Java was through LWJGL or JOCL.

libGDX was built on LWJGL, so my first instinct was to see if I could access that built in OpenCL support through the libGDX library, however, after looking around, I found nothing about this whatsoever!

My question is, can I access OpenCl through the libGDX library, and if so, how?

If I can't access LWJGL's OpenCl implementation, should I use JOCL to access GPU mathematical computations, or should I add a second library of LWJGL into my libGDX application?