Time and Benchmark
Set of functions to time measurement and Benchmark.
Initialization
The best way to initialize all Ikarus functions is to call MEM_InitAll()
in the Init_Global()
initialization function.
Warning
If you want to use Ikarus in Gothic 1, it is best to define your own Init_Global()
function and call it from every world initialization function.
Implementation
Time functions
MEM_GetSystemTime
MEM_GetSystemTime
Returns the elapsed time since Gothic started.
The function returns the elapsed time since the start of Gothic in milliseconds. This value is used for timing measurements, in the BenchmarkMS
functions.
MEM_GetPerformanceCounter
MEM_GetPerformanceCounter
Call to the WinAPI QueryPerformanceCounter
function.
The function returns a value representing the number of elapsed ticks since the system was started. This value is used for timing measurements, in the BenchmarkPC
functions.
Benchmark functions
Tip
For reliable results, avoid measuring a single run of a function; instead, measure the total duration of multiple runs (e.g., 1000). This is crucial, especially for very fast functions, as a single run can distort the measurement. Use _N
benchmark functions to include a parameter specifying the number of runs for function f
.
Choose the parameter n
to ensure meaningful results. If n
executions take less than a millisecond, obtaining a return value in milliseconds has no sense. For very fast functions, the time spent in the benchmark function, not in f
, significantly affects the measurement, falsifying the result. Reliable measurements are achievable only for functions with sufficient slowness.
For reference, here is a timing for some operations (in nanoseconds, i.e., billionths of a second):
MEM_BenchmarkMS
MEM_BenchmarkMS
Benchmark of the execution time for a specified function. (Milliseconds)
var func f
Function to benchmark
Return value
The function returns the duration of a function execution in milliseconds.
MEM_BenchmarkMMS
MEM_BenchmarkMMS
Benchmark of the execution time for a specified function. (microseconds)
var func f
Function to benchmark
Return value
The function returns the duration of a function execution in microseconds.
MEM_BenchmarkPC
MEM_BenchmarkPC
Benchmark of the execution time for a specified function, using the Performancecounter.
var func f
Function to benchmark
Return value
The function returns the number of Performancecounter ticks the function needs.
MEM_BenchmarkMS_N
MEM_BenchmarkMS_N
MEM_BenchmarkMS
, but with the parameter to specify the number of function runs.
var func f
Function to benchmarkvar int n
Number of runs
Return value
The function returns a summed duration of multiple (n
) runs of the function in milliseconds.
MEM_BenchmarkMMS_N
MEM_BenchmarkMMS_N
MEM_BenchmarkMMS
, but with the parameter to specify the number of function runs.
var func f
Function to benchmarkvar int n
Number of runs
Return value
The function returns a summed duration of multiple (n
) runs of the function in microseconds.
MEM_BenchmarkPC_N
MEM_BenchmarkPC_N
MEM_BenchmarkPC
, but with the parameter to specify the number of function runs.
var func f
Function to benchmarkvar int n
Number of runs
Return value
The function returns a summed number of Performancecounter ticks needed to execute function multiple (n
) times.