GetThreadTimes (kernel32)
Last changed: -220.233.201.35

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Summary

C# Signature:

[DllImport("kernel32.dll", SetLastError=true)]
static extern bool GetThreadTimes(IntPtr hThread, out long lpCreationTime,
   out long lpExitTime, out long lpKernelTime, out long lpUserTime);

User-Defined Types:

None.

Notes:

Although the API returns times in 100 nanosecond units, the precision is only to that of the process scheduler, about 15 milliseconds (depending on OS version). So don't expect pinpoint accuracy on short running functions.

The original API defined the return values as FILETIME rather than long, but long appears to be compatible with FILETIME and can be easier to deal with.

Tips & Tricks:

Please add some!

Sample Code:

long l,KernelStart,UserStart;
GetThreadTimes(GetCurrentThread(),out l,out l,out KernelStart,out UserStart);
try
{
    FunctionToProfile(); // Whatever function you want to measure CPU usage of.
}
finally
{
    long KernelEnd,UserEnd;
    GetThreadTimes(GetCurrentThread(),out l,out l,out KernelEnd,out UserEnd);
    long TimeUsed=(KernelEnd-KernelStart)+(UserEnd-UserStart);
    Console.WriteLine("Function used {0}ms CPU",TimeUsed/10000.0);
}


Please add some!

Alternative Managed API:

Do you know one? Please contribute it!

Documentation