Based on the graph available in the post, the only difference I see between C and C++ performance is on low n. At higher values of n, they have the same perfor

Based on the graph available in the post, the only difference I see between C and C++ performance is on low n. At higher values of n, they have the same performance (as expected). That discrepancy is easily explained by considering start-up time, which C++ could certainly suffer from. Combine that with the consideration that the values for n where the two differ result in a computation time < ~10ms, which is about the range where startup time is going to significantly impact results. This is also easy to see by looking at the second derivative of the graphs. When n is large enough to outweigh startup time, the graph should be linear. The areas where the second derivative is non-zero indicate that start-up time is affecting results. You can see that all the languages have some kind of startup time impacting results. Java in particular has the same performance as C/C++ under this test, but has a significantly larger startup time. Really experiments like this should split the results to explicitly show these two aspects of performance. Measure startup time and measure the time running the actual test code separately. Though that might be more challenging on JIT'd languages.