iOS app launch time measurement

Question

How can I count the time it takes from the moment the user presses the launch button on the home screen until the moment the app is active (for example, until the viewDidAppear

Answer 1

There is a possibility to get process start time with C api

#import 

static CFTimeInterval processStartTime() {
    size_t len = 4;
    int mib[len];
    struct kinfo_proc kp;

    sysctlnametomib("kern.proc.pid", mib, &len);
    mib[3] = getpid();
    len = sizeof(kp);
    sysctl(mib, 4, &kp, &len, NULL, 0);

    struct timeval startTime = kp.kp_proc.p_un.__p_starttime;
    return startTime.tv_sec + startTime.tv_usec / 1e6;
}

You can also do this in swift, but that would be wordier. Example can be found in CwlUtils.

After that you can calculate startup time with the different ways.

For example I do:

let currentTime = CFAbsoluteTimeGetCurrent() + kCFAbsoluteTimeIntervalSince1970
let startupTime = currentTime - processStartTime()

Full post about that I found here