I started working with OpenCL recently on the project at work. It's quite exhausting to learn initially since OpenCL has quite steep learning curve. However, once you have started to picked up some of the core concept, it could be quite interesting. Also, you will add another valuable tool to your programming arsenal, especially in the aspect of performance and speedup. You will start to be able to exploit not just CPU but also any other computing device that exist on the system like GPU quite conveniently.
Here's summary and pointers of how to get started with it from what I note so far.
You can get an initial overview from the surces below :
- OpenCL Overview (PDF) from its official site is quite easy to skim. Just skim it and don't bother with the details like code, it will be clearer soon
- Also, skimming the Official Specification and Quick Reference Card could help too to get an initial picture of what it is
As usual, google search and some blog entries would not hurt too. However, it's better not to take too much time researching things online since I think your time is better spend reading the book below.
Book : OpenCL in Action
There is not many technical book that you can enjoy reading cover to cover. This one is one of them. It's better you read from beginning to end serially. It build up from chapter to chapter. Also, it does not cross reference things too much between materials which could be annoying on some technical books. The materials coverage is very good, from the history, introduction to advanced topics.
If you have some questions on your mind from reading other sources previously, there is a good chance that you will start to piece things together when reading this book. It gives a good foundation for understanding why OpenCL is the way it is. OpenCL syntax and functions will still be quite overwhelming even after you finished with the book but knowing the concept behind will make it much more manageable.
I find the highlights of the book is its use of analogies that helps a lot in explaining the abstract concept and architecture of OpenCL.
Revisit Specification and Reference Card
If you have skimmed the specification and reference card above, it's time to revisit it again. You will now find it much more clearer now and they are starting to be more useful. It will also add more details from what is covered on the book. Personally, I really like the layout on reference card which help in getting a good high level picture of different parts of OpenCL with it's colorful boxes and groupings.
At this point, you can start to work on your specific issues and continue learning from there. As usual, after the initial learning, the actual work is where we will learn most. This is especially true in complex technology like OpenCL.