I was recently invited to deliver a talk at an upcoming conference, and that meant I had to come up with a topic. I wrote up a talk description, but when I was done, I decided that I wanted to save it for this year’s C++ and Beyond.  As a result, I now have a topic to announce for this December’s C&B:

Concurrent Data Structures and Standard C++

Concurrent data structures permit multiple writers to simultaneously modify a single data structure. Used properly, they can avoid scalability bottlenecks in multithreaded systems. Used improperly, they can decrease program performance.

There are no concurrent data structures in the C++98 standard library. The C++11 standard library is similarly bare, and C++14 is unlikely to change that.  Nevertheless, concurrent data structures for C++ developers are widely available from sources such as Microsoft’s PPL, Intel’s TBB, and Boost. In this talk, I’ll examine the motivation and use cases for concurrent data structures, discuss their limitations, survey offerings common to PPL and TBB, and contrast concurrent APIs with those of seemingly similar serial counterparts (e.g., concurrent_vector vs. std::vector). I’ll also explain why writing your own concurrent data structure is much more complicated and error-prone than most people initially imagine.  (If you’re not familiar with the ABA problem, this presentation will explain why you should be.)


PS - I still don’t know what I’ll talk about at the other conference :-)