How Can I Accurately Measure the Execution Time of a C Function on Linux?

Measuring Execution Time of a Function in C

To gauge the execution time of a specific function in your C program, multiple time-measuring techniques are available. However, for an accurate measurement on a Linux system, Boost.Chrono's process_user_cpu_clock function is recommended.

This function pinpoints the time the CPU spends executing the specified function, excluding any time spent on other processes or system tasks. Here's a code snippet illustrating its usage:

#include <boost/chrono/process_time_clock.hpp>

using namespace boost::chrono;

boost::chrono::process_time_clock::time_point start, end;

// Function whose execution time is being measured
void my_function() { /* ... */ }

start = process_user_cpu_clock::now();
my_function();
end = process_user_cpu_clock::now();

duration<double> total_time = end - start;

cout << "Execution time: " << total_time.count() << " seconds" << endl;

In the code above, the start and end variables capture the CPU time at the start and end of the my_function call, respectively. The total_time variable then stores the time difference, which represents the function's execution time.

Note that the above method measures the user-mode CPU time and does not include time spent in the operating system or other processes. Additionally, it's important to consider the possibility of context switches and I/O operations, which may affect the accuracy of the measurement.

The above is the detailed content of How Can I Accurately Measure the Execution Time of a C Function on Linux?. For more information, please follow other related articles on the PHP Chinese website!