Why does Batch Analysis not make use of all available processing cores?

Why does Batch Analysis not make use of all available processing cores?

As of Columbus version 2.9.0 (Acapella 5.0.x.120997), the way in which Columbus utilises the availalbe number of cores has been optimized, specifically with regard to servers that have hyper-threading enabled.

The optimum number of worker threads that Columbus uses depends primarily on the number of physical cores. If hyper-threading is enabled, the number of logical cores is doubled, but Columbus performance benchmarks have shown that there is very little benefit to maxing-out logical/hyper-threaded CPU-s, it simply overloads the server resources without significant speedup. The default worker thread number calculations now uses the number of physical cores plus 20% of logical cores if hyper-threading is enabled. So task manager programs (such as top) may show that Acapella does not use 100% of logical cpu-s, this is normal.