CPU Time & Taskkill

CPU Time is the amount of time that the central processing unit (CPU) spends executing instructions of a computer program. It is a high-level metric that indicates how much processing power is being utilized by a program. Taskkill is a command-line utility in Windows that can be used to terminate running processes. It can be useful for freeing up system resources and troubleshooting issues with errant programs.

Getting CPU Time in Windows

In Windows, you can use the GetProcessTimes function in the Windows API to retrieve information about a process, including its CPU time. Here is an example of how to use this function in C++:

#include <windows.h>

int main() {
    HANDLE process = GetCurrentProcess();  // Get handle to current process
    FILETIME creation_time, exit_time, kernel_time, user_time;
    
    // Get process times
    GetProcessTimes(process, &creation_time, &exit_time, &kernel_time, &user_time);
    
    // Calculate CPU time by adding kernel time and user time
    ULARGE_INTEGER kernel_time_ul, user_time_ul;
    kernel_time_ul.LowPart = kernel_time.dwLowDateTime;
    kernel_time_ul.HighPart = kernel_time.dwHighDateTime;
    user_time_ul.LowPart = user_time.dwLowDateTime;
    user_time_ul.HighPart = user_time.dwHighDateTime;
    ULONGLONG cpu_time = kernel_time_ul.QuadPart + user_time_ul.QuadPart;
    
    // Print CPU time in milliseconds
    printf("CPU time: %llu ms", cpu_time / 10000);
    
    return 0;
}

Using Taskkill

Taskkill can be useful for terminating processes that are causing issues or using too many system resources. Here are some examples of how to use taskkill:

taskkill /IM notepad.exe          // Terminates all instances of Notepad
taskkill /PID 1234 /F             // Forces termination of process with PID 1234
taskkill /S computer /U username /P password /IM chrome.exe  // Terminates Chrome on a remote computer

The /IM option specifies the image name of the process (e.g. "chrome.exe"), while the /PID option specifies the process ID. The /F option forces termination of the process, while the /S, /U, and /P options specify the name of a remote computer, the username to use, and the password to use, respectively. Taskkill can also be used in scripts and automated processes to help manage system resources.