Now there are four cores – and better ones – I felt the need to run our VIPS benchmarks to see how well the cores can work together. This is CPU-bound so is not affected by the micro-SD card speeds. Here are my results using vips-7.42.3:
Threads, time(s), speed-up
1, 92, 1
2, 48.2, 1.9 x
3, 32.5, 2.8 x
4, 23.2, 3.96 x
I ran them in console mode so there were no desktop threads running (although the little CPU meter is interesting if you do that – showing 25% 50% 75% 100% roughly as you increase the cores used.
Conclusion: the Pi2 is about a quarter of the speed of an old core-2 duo type core and certainly slower than the ARM A15 found in modern tablets/chromebooks. Parallel processing on the Pi does work well however with a 4 core speed-up of 3.96 times.
Kirk