Package bottleneck allows do detect bottlenecks in your code. Package uses atomic to minimize impact on performance. Bottleneck info returning by `Stats` function is eventually consistent. Which operation takes more time? The example below proves that creating and filling an array with random numbers takes less time than sorting. The output is: The example below starts two goroutines. The first one is imitating a worker with two complex jobs. The second one monitors worker's executions. It shows percentage, number of calls and total execution time per each job. A fragment of output: