[xaa]

Yes, every time I hear people talking about how evil or difficult threads are, I just think back to my frequent use of OpenMP. It is really quite easy to take a single-threaded program and make it multithreaded with OMP -- so long as the jobs only read, and do not write shared state.

Usually I will write a program that does the following:

1. Initialize global read-only data structures

2. Parallelize jobs across STDIN lines (or whatever)

3. Output results within a #pragma omp critical block

It works wonders, and is literally 5 additional lines of code to make a single-threaded program multithreaded with OMP. But only for some types of program. The concept is very similar to what GNU parallel does.

In short, threads are not the problem per se, they are just the wrong tool for the job if you have a multiple-readers multiple-writers situation. Message passing, databases, or something else are more appropriate in those cases. But you will pry my read only shared memory space out of my cold, dead hands.

[imtringued]

Using OMP is incredibly easy but in my experience it sometimes leaves up to 20% performance on the table vs doing and tuning everything manually.