How many threads does it take to make them a bad choice?

Question

I have to write a not-so-large program in C++, using boost::thread.

The problem at hand, is to process a large (maybe thousands or tens of thousands. Hundreds and millon

Answer 1

Use a thread pool instead of creating a thread for each file. You can easily to adjust the number of threads once you write your solution. If the jobs are independed from each other, i'd say the number of threads should be equal to number of cores/cpus.