CPU Intensive Calculation Examples?
A few easy examples of CPU-intensive tasks:
- searching for prime numbers (involves lots of BigInteger divisions)
- calculating large factorials e.g. 2000! ((involves lots of BigInteger multiplications)
- many Math.tan() calculations (this is interesting because Math.tan is native, so you're using two call stacks: one for Java calls, the other for C calls.)
Multiply two matrices. The matrices should be huge and stored on the disk.
String search. Or, index a huge document (detect and count the occurrence of each word or strings of alphabets) For example, you can index all of the identifiers in the source code of a large software project.
Calculate pi.
Rotate a 2D matrix, or an image.
Compress some huge files.
...
The CPU soak test for the PDP-11 was tan(atan(tan(atan(...))) etc. Works the FPU pretty hard and also the stack and registers.