Most likely every programmer knows python is a low efficiency language, but how slow it is? See this picture:

The author compared virtually all languages considering three variables: energy consumption, memory consumption and execution time. Java and C are doing very well in energy and time. As to python, the numbers are not ideal as python is interpreted a language and using GIL mechanism.

I also did a experiment by myself, where I picked up k numbers from n numbers(n is much larger than k). I compared three languages: python, c and cuda with single and multi-threads. The column name (k|n) means k from n. Here is my result:

C is much faster than python, specially when data is raising fast.Python’s multi-threads is significantly better than single thread. However, I don’t know why C’s multi-threads is almost as same as the single thread.In multi-threads C, I found CPU usage is lower than 30% for each thread.Perhaps create threads takes time. Since I used clock object in C to calc time costing, it got the user time rather than cpu time.(real < user when parallely running). If we want to get real time, we should use clock_gettime(CLOCK_MONOTONIC, &start);Credit: [Dr.Greg Wolffe] . As to Cuda, in this case, no matter how data size raising, the time didn’t change much, although in the small data size, it didn’t run very fast compared with C.

You can find more detail on my Github.

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