Time a function

From Rosetta Code
Task
Time a function
You are encouraged to solve this task according to the task description, using any language you may know.
Task

Write a program which uses a timer (with the least granularity available on your system) to time how long a function takes to execute.

Whenever possible, use methods which measure only the processing time used by the current process; instead of the difference in system time between start and finish, which could include time used by other processes on the computer.

This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.

8051 Assembly[edit]

Using a timer requires knowledge on two things: the oscillator frequency (which limits the maximum precision) and the desired precision. This code uses a common crystal of 11.0592MHz - but provides values for a few others as examples. This code also uses a precision of 4 bits (2^(-4) = 0.0625 seconds). Those familiar with binary can think of this as a right shift of 4 of the multi-byte value, where the low 4 bits represent the fraction of a second, and the remaining bits represent whole seconds. The maximum time value depends on the number of bytes used and the precision. For x bytes and p precision, the maximum value you can count to is (256^x - 1) * 2^(-p).

TC	EQU	8 ; number of counter registers
TSTART EQU 08h ; first register of timer counter
TEND EQU TSTART + TC - 1 ; end register of timer counter
; Note: The multi-byte value is stored in Big-endian
 
; Some timer reloads
_6H EQU 085h ; 6MHz
_6L EQU 0edh
_12H EQU 00bh ; 12MHz
_12L EQU 0dbh
_110592H EQU 01eh ; 11.0592MHz
_110592L EQU 0ffh
 
; How to calculate timer reload (e.g. for 11.0592MHz):
; Note: 1 machine cycle takes 12 oscillator periods
; 11.0592MHz / 12 * 0.0625 seconds = 57,600 cycles = e100h
; ffffh - e100h = NOT e100h = 1effh
 
; assuming a 11.0592MHz crystal
TIMERH EQU _110592H
TIMERL EQU _110592L
 
;; some timer macros (using timer0)
start_timer macro
setb tr0
endm
stop_timer macro
clr tr0
endm
reset_timer macro
mov tl0, #TIMERL
mov th0, #TIMERH
endm
 
increment_counter macro ;; increment counter (multi-byte increment)
push psw
push acc
push 0 ; r0
mov r0, #TEND+1
setb c
inc_reg:
dec r0
clr a
addc a, @r0
mov @r0, a
jnc inc_reg_ ; end prematurally if the higher bytes are unchanged
cjne r0, #TSTART, inc_reg
inc_reg_:
; if the carry is set here then the multi byte value has overflowed
pop 0
pop acc
pop psw
endm
 
ORG RESET
jmp init
ORG TIMER0
jmp timer_0
 
timer_0: ; interrupt every 6.25ms
stop_timer ; we only want to time the function
reset_timer
increment_counter
start_timer
reti
 
init:
mov sp, #TEND
setb ea ; enable interrupts
setb et0 ; enable timer0 interrupt
mov tmod, #01h ; timer0 16-bit mode
reset_timer
 
; reset timer counter registers
clr a
mov r0, #TSTART
clear:
mov @r0, a
inc r0
cjne r0, #TEND, clear
 
start_timer
call function ; the function to time
stop_timer
 
; at this point the registers from TSTART
; through TEND indicate the current time
; multiplying the 8/16/24/etc length value by 0.0625 (2^-4) gives
; the elapsed number of seconds
; e.g. if the three registers were 02a0f2h then the elapsed time is:
; 02a0f2h = 172,274 and 172,274 * 0.0625 = 10,767.125 seconds
;
; Or alternatively:
; (high byte) 02h = 2 and 2 * 2^(16-4) = 8192
; (mid byte) a0h = 160 and 160 * 2^(8-4) = 2560
; (low byte) f2h = 242 and 242 * 2^(0-4) = 15.125
; 8192 + 2560 + 15.125 = 10,767.125 seconds
 
jmp $
 
function:
; do whatever here
ret
 
END
 

ACL2[edit]

(time$ (nthcdr 9999999 (take 10000000 nil)))

Output (for Clozure):

; (EV-REC *RETURN-LAST-ARG3* ...) took 
; 2.53 seconds realtime, 2.48 seconds runtime
; (160,001,648 bytes allocated).
(NIL)

Ada[edit]

with Ada.Calendar; use Ada.Calendar;
with Ada.Text_Io; use Ada.Text_Io;
 
procedure Query_Performance is
type Proc_Access is access procedure(X : in out Integer);
function Time_It(Action : Proc_Access; Arg : Integer) return Duration is
Start_Time : Time := Clock;
Finis_Time : Time;
Func_Arg : Integer := Arg;
begin
Action(Func_Arg);
Finis_Time := Clock;
return Finis_Time - Start_Time;
end Time_It;
procedure Identity(X : in out Integer) is
begin
X := X;
end Identity;
procedure Sum (Num : in out Integer) is
begin
for I in 1..1000 loop
Num := Num + I;
end loop;
end Sum;
Id_Access : Proc_Access := Identity'access;
Sum_Access : Proc_Access := Sum'access;
 
begin
Put_Line("Identity(4) takes" & Duration'Image(Time_It(Id_Access, 4)) & " seconds.");
Put_Line("Sum(4) takes:" & Duration'Image(Time_It(Sum_Access, 4)) & " seconds.");
end Query_Performance;

Example[edit]

Identity(4) takes 0.000001117 seconds.
Sum(4) takes: 0.000003632 seconds.

Aime[edit]

integer
identity(integer x)
{
return x;
}
 
 
integer
sum(integer c)
{
integer s;
 
s = 0;
while (c) {
s += c;
c -= 1;
}
 
return s;
}
 
 
real
time_f(integer (*fp) (integer), integer fa)
{
date f, s;
time t;
 
d_now(s);
 
fp(fa);
 
d_now(f);
 
t_ddiff(t, f, s);
 
return t_microsecond(t) / 1000000r;
}
 
 
integer
main(void)
{
o_real(6, time_f(identity, 1));
o_text(" seconds\n");
o_real(6, time_f(sum, 1000000));
o_text(" seconds\n");
 
return 0;
}

AutoHotkey[edit]

System time[edit]

Uses system time, not process time

MsgBox % time("fx")
Return
 
fx()
{
Sleep, 1000
}
 
time(function, parameter=0)
{
SetBatchLines -1 ; don't sleep for other green threads
StartTime := A_TickCount
%function%(parameter)
Return ElapsedTime := A_TickCount - StartTime . " milliseconds"
}

Using QueryPerformanceCounter[edit]

QueryPerformanceCounter allows even more precision:

MsgBox % time("fx")
 
time(function, parameter=0){
SetBatchLines -1
DllCall("QueryPerformanceCounter", "Int64*", CounterBefore)
DllCall("QueryPerformanceFrequency", "Int64*", Freq)
%function%(parameter)
DllCall("QueryPerformanceCounter", "Int64*", CounterAfter)
return (CounterAfter-CounterBefore)/Freq * 1000 " milliseconds"
}
 
fx(){
Sleep 1000
}

BaCon[edit]

The BaCon TIMER function keeps track of time spent running, in milliseconds (which is also the time unit used by SLEEP). This is not process specific, but a wall clock time counter which starts at 0 during process initialization. As BaCon can easily use external C libraries, process specific CLOCK_PROCESS_CPUTIME_ID clock_gettime could also be used.

' Time a function
SUB timed()
SLEEP 7000
END SUB
 
st = TIMER
timed()
et = TIMER
PRINT st, ", ", et
Output:
prompt$ ./time-function
0, 7000

BASIC[edit]

Works with: QBasic
DIM timestart AS SINGLE, timedone AS SINGLE, timeelapsed AS SINGLE
 
timestart = TIMER
SLEEP 1 'code or function to execute goes here
timedone = TIMER
 
'midnight check:
IF timedone < timestart THEN timedone = timedone + 86400
timeelapsed = timedone - timestart

See also: BBC BASIC, PureBasic.

Batch File[edit]

Granularity: hundredths of second.

 
@echo off
Setlocal EnableDelayedExpansion
 
call :clock
 
::timed function:fibonacci series.....................................
set /a a=0 ,b=1,c=1
:loop
if %c% lss 2000000000 echo %c% & set /a c=a+b,a=b, b=c & goto loop
::....................................................................
 
call :clock
 
echo Function executed in %timed% hundredths of second
goto:eof
 
:clock
if not defined timed set timed=0
for /F "tokens=1-4 delims=:.," %%a in ("%time%") do (
set /A timed = "(((1%%a - 100) * 60 + (1%%b - 100)) * 60 + (1%%c - 100)) * 100 + (1%%d - 100)- %timed%"
)
goto:eof
 

BBC BASIC[edit]

start%=TIME:REM centi-second timer
REM perform processing
lapsed%=TIME-start%

Bracmat[edit]

( ( time
= fun funarg t0 ret
.  !arg:(?fun.?funarg)
& clk$:?t0
& !fun$!funarg:?ret
& (!ret.flt$(clk$+-1*!t0,3) s)
)
& ( fib
=
.  !arg:<2&1
| fib$(!arg+-1)+fib$(!arg+-2)
)
& time$(fib.30)
)

Output:

1346269.5,141*10E0 s

C[edit]

Works with: POSIX version .1-2001

On some system (like GNU/Linux) to be able to use the clock_gettime function you must link with the rt (RealTime) library.

CLOCK_PROCESS_CPUTIME_ID is preferred when available (eg. Linux kernel 2.6.12 up), being CPU time used by the current process. (CLOCK_MONOTONIC generally includes CPU time of unrelated processes, and may be drifted by adjtime().)

#include <stdio.h>
#include <time.h>
 
int identity(int x) { return x; }
 
int sum(int s)
{
int i;
for(i=0; i < 1000000; i++) s += i;
return s;
}
 
#ifdef CLOCK_PROCESS_CPUTIME_ID
/* cpu time in the current process */
#define CLOCKTYPE CLOCK_PROCESS_CPUTIME_ID
#else
/* this one should be appropriate to avoid errors on multiprocessors systems */
#define CLOCKTYPE CLOCK_MONOTONIC
#endif
 
double time_it(int (*action)(int), int arg)
{
struct timespec tsi, tsf;
 
clock_gettime(CLOCKTYPE, &tsi);
action(arg);
clock_gettime(CLOCKTYPE, &tsf);
 
double elaps_s = difftime(tsf.tv_sec, tsi.tv_sec);
long elaps_ns = tsf.tv_nsec - tsi.tv_nsec;
return elaps_s + ((double)elaps_ns) / 1.0e9;
}
 
int main()
{
printf("identity (4) takes %lf s\n", time_it(identity, 4));
printf("sum (4) takes %lf s\n", time_it(sum, 4));
return 0;
}

C++[edit]

#include <ctime>
#include <iostream>
using namespace std;
 
int identity(int x) { return x; }
int sum(int num) {
for (int i = 0; i < 1000000; i++)
num += i;
return num;
}
 
double time_it(int (*action)(int), int arg) {
clock_t start_time = clock();
action(arg);
clock_t finis_time = clock();
return ((double) (finis_time - start_time)) / CLOCKS_PER_SEC;
}
 
int main() {
cout << "Identity(4) takes " << time_it(identity, 4) << " seconds." << endl;
cout << "Sum(4) takes " << time_it(sum, 4) << " seconds." << endl;
return 0;
}

Example[edit]

Identity(4) takes 0 seconds.
Sum(4) takes 0.01 seconds.

C#[edit]

Using Stopwatch.

using System;
using System.Linq;
using System.Threading;
using System.Diagnostics;
 
class Program {
static void Main(string[] args) {
Stopwatch sw = new Stopwatch();
 
sw.Start();
DoSomething();
sw.Stop();
 
Console.WriteLine("DoSomething() took {0}ms.", sw.Elapsed.TotalMilliseconds);
}
 
static void DoSomething() {
Thread.Sleep(1000);
 
Enumerable.Range(1, 10000).Where(x => x % 2 == 0).Sum(); // Sum even numers from 1 to 10000
}
}

Using DateTime.

using System;
using System.Linq;
using System.Threading;
 
class Program {
static void Main(string[] args) {
DateTime start, end;
 
start = DateTime.Now;
DoSomething();
end = DateTime.Now;
 
Console.WriteLine("DoSomething() took " + (end - start).TotalMilliseconds + "ms");
}
 
static void DoSomething() {
Thread.Sleep(1000);
 
Enumerable.Range(1, 10000).Where(x => x % 2 == 0).Sum(); // Sum even numers from 1 to 10000
}
}

Output:

DoSomething() took 1071,5408ms

Clojure[edit]

 
(defn fib []
(map first
(iterate
(fn [[a b]] [b (+ a b)])
[0 1])))
 
(time (take 100 (fib)))
 

Output:

"Elapsed time: 0.028 msecs"
(0 1 1 2 3 5 8 13 21 34 55 89 144 233 377 610 987 1597 2584 4181)

Common Lisp[edit]

Common Lisp provides a standard utility for performance measurement, time:

CL-USER> (time (reduce #'+ (make-list 100000 :initial-element 1)))
Evaluation took:
0.151 seconds of real time
0.019035 seconds of user run time
0.01807 seconds of system run time
0 calls to %EVAL
0 page faults and
2,400,256 bytes consed.

(The example output here is from SBCL.)

However, it merely prints textual information to trace output, so the information is not readily available for further processing (except by parsing it in a CL-implementation-specific manner).

The functions get-internal-run-time and get-internal-real-time may be used to get time information programmatically, with at least one-second granularity (and usually more). Here is a function which uses them to measure the time taken for one execution of a provided function:

(defun timings (function)
(let ((real-base (get-internal-real-time))
(run-base (get-internal-run-time)))
(funcall function)
(values (/ (- (get-internal-real-time) real-base) internal-time-units-per-second)
(/ (- (get-internal-run-time) run-base) internal-time-units-per-second))))
 
CL-USER> (timings (lambda () (reduce #'+ (make-list 100000 :initial-element 1))))
17/500
7/250

D[edit]

import std.stdio, std.datetime;
 
int identity(int x) {
return x;
}
 
int sum(int num) {
foreach (i; 0 .. 100_000_000)
num += i;
return num;
}
 
double timeIt(int function(int) func, int arg) {
StopWatch sw;
sw.start();
func(arg);
sw.stop();
return sw.peek().usecs / 1_000_000.0;
}
 
void main() {
writefln("identity(4) takes %f6 seconds.", timeIt(&identity, 4));
writefln("sum(4) takes %f seconds.", timeIt(&sum, 4));
}
Output:
identity(4) takes 0.0000016 seconds.
sum(4) takes 0.522065 seconds.

Using Tango[edit]

 
import tango.io.Stdout;
import tango.time.Clock;
 
int identity (int x)
{
return x;
}
 
int sum (int num)
{
for (int i = 0; i < 1000000; i++)
num += i;
return num;
}
 
double timeIt(int function(int) func, int arg)
{
long before = Clock.now.ticks;
func(arg);
return (Clock.now.ticks - before) / cast(double)TimeSpan.TicksPerSecond;
}
 
void main ()
{
Stdout.format("Identity(4) takes {:f6} seconds",timeIt(&identity,4)).newline;
Stdout.format("Sum(4) takes {:f6} seconds",timeIt(&sum,4)).newline;
}
 

E[edit]

Translation of: Java
— E has no standardized facility for CPU time measurement; this
Works with: E-on-Java
.
def countTo(x) {
println("Counting...")
for _ in 1..x {}
println("Done!")
}
 
def MX := <unsafe:java.lang.management.makeManagementFactory>
def threadMX := MX.getThreadMXBean()
require(threadMX.isCurrentThreadCpuTimeSupported())
threadMX.setThreadCpuTimeEnabled(true)
 
for count in [10000, 100000] {
def start := threadMX.getCurrentThreadCpuTime()
countTo(count)
def finish := threadMX.getCurrentThreadCpuTime()
println(`Counting to $count takes ${(finish-start)//1000000}ms`)
}

Elixir[edit]

Translation of: Erlang

tc/1

iex(10)> :timer.tc(fn -> Enum.each(1..100000, fn x -> x*x end) end)
{236000, :ok}

tc/2

iex(11)> :timer.tc(fn x -> Enum.each(1..x, fn y -> y*y end) end, [1000000])
{2300000, :ok}

tc/3

iex(12)> :timer.tc(Enum, :to_list, [1..1000000])
{224000,
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22,
23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41,
42, 43, 44, 45, 46, 47, 48, 49, ...]}

Erlang[edit]

Erlang's timer module has three implementations of the tc function.

tc/1 takes a 0-arity function and executes it:

 
5> {Time,Result} = timer:tc(fun () -> lists:foreach(fun(X) -> X*X end, lists:seq(1,100000)) end).
{226391,ok}
6> Time/1000000. % Time is in microseconds.
0.226391
7> % Time is in microseconds.
 

tc/2 takes an n-arity function and its arguments:

 
9> timer:tc(fun (X) -> lists:foreach(fun(Y) -> Y*Y end, lists:seq(1,X)) end, [1000000]).
{2293844,ok}
 

tc/3 takes a module name, function name and the list of arguments to the function:

 
8> timer:tc(lists,seq,[1,1000000]).
{62370,
[1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,
23,24,25,26,27|...]}
 

Euphoria[edit]

atom t
t = time()
some_procedure()
t = time() - t
printf(1,"Elapsed %f seconds.\n",t)

F#[edit]

The .Net framework provides a Stopwatch class which provides a performance counter.

 
open System.Diagnostics
let myfunc data =
let timer = new Stopwatch()
timer.Start()
let result = data |> expensive_processing
timer.Stop()
printf "elapsed %d ms" timer.ElapsedMilliseconds
result
 

Factor[edit]

[ 10000 iota sum drop ] time

Output:

Running time: 0.002888635 seconds

Additional information was collected.
dispatch-stats.  - Print method dispatch statistics
gc-events.       - Print all garbage collection events
gc-stats.        - Print breakdown of different garbage collection events
gc-summary.      - Print aggregate garbage collection statistics

Forth[edit]

Works with: GNU Forth
: time: ( "word" -- )
utime 2>R ' EXECUTE
utime 2R> D-
<# # # # # # # [CHAR] . HOLD #S #> TYPE ." seconds" ;
 
1000 time: MS \ 1.000081 seconds ok

Fortran[edit]

Works with: Gfortran
version 4.4.5 (Debian 4.4.5-8) on x86_64-linux-gnu
 
c The subroutine to analyze
subroutine do_something()
c For testing we just do nothing for 3 seconds
call sleep(3)
return
end
 
c Main Program
program timing
integer(kind=8) start,finish,rate
call system_clock(count_rate=rate)
call system_clock(start)
c Here comes the function we want to time
call do_something()
call system_clock(finish)
write(6,*) 'Elapsed Time in seconds:',float(finish-start)/rate
return
end
 

FreeBASIC[edit]

' FB 1.05.0 Win64
 
Function sumToLimit(limit As UInteger) As UInteger
Dim sum As UInteger = 0
For i As UInteger = 1 To limit
sum += i
Next
Return sum
End Function
 
Dim As Double start = timer
Dim limit As UInteger = 100000000
Dim result As UInteger = sumToLimit(limit)
Dim ms As UInteger = Int(1000 * (timer - start) + 0.5)
Print "sumToLimit("; Str(limit); ") = "; result
Print "took "; ms; " milliseconds to calculate"
Print
Print "Press any key to quit"
Sleep
Output:
sumToLimit(100000000) = 5000000050000000
took 314 milliseconds to calculate

GAP[edit]

# Return the time passed in last function
time;

Go[edit]

go test[edit]

The Go command line tool go test includes benchmarking support. Given a package with functions:

package empty
 
func Empty() {}
 
func Count() {
// count to a million
for i := 0; i < 1e6; i++ {
}
}

the following code, placed in a file whose name ends in _test.go, will time them:

package empty
 
import "testing"
 
func BenchmarkEmpty(b *testing.B) {
for i := 0; i < b.N; i++ {
Empty()
}
}
 
func BenchmarkCount(b *testing.B) {
for i := 0; i < b.N; i++ {
Count()
}
}

go test varies b.N to get meaningful resolution. Example:

$ go test -bench=.
testing: warning: no tests to run
PASS
BenchmarkEmpty	2000000000	         0.30 ns/op
BenchmarkCount	   10000	    298734 ns/op
ok  		3.642s

The first number is the value of b.N chosen and the second the average time per iteration. The testing package can optionally include memory use and throughput benchmarks.

There is also a standard tool to compare the multiple benchmark outputs (installable via go get golang.org/x/tools/cmd/benchcmp).

testing.Benchmark[edit]

The benchmarking features of the testing package are exported for use within a Go program.

package main
 
import (
"fmt"
"testing"
)
 
func empty() {}
 
func count() {
for i := 0; i < 1e6; i++ {
}
}
 
func main() {
e := testing.Benchmark(func(b *testing.B) {
for i := 0; i < b.N; i++ {
empty()
}
})
c := testing.Benchmark(func(b *testing.B) {
for i := 0; i < b.N; i++ {
count()
}
})
fmt.Println("Empty function: ", e)
fmt.Println("Count to a million:", c)
fmt.Println()
fmt.Printf("Empty: %12.4f\n", float64(e.T.Nanoseconds())/float64(e.N))
fmt.Printf("Count: %12.4f\n", float64(c.T.Nanoseconds())/float64(c.N))
}
Output:
Empty function:     2000000000	         0.80 ns/op
Count to a million:     2000	    796071 ns/op

Empty:       0.7974
Count:  796071.6555

Alternative technique[edit]

The go test command and the testing package are the preferred techniques for benchmarking or timing any Go code. Ignoring the well-tested and carefully crafted standard tools though, here is a simplistic alternative:

As the first line of the function you wish to time, use defer with an argument of time.Now() to print the elapsed time to the return of any function. For example, define the function from as shown below. It works because defer evaluates its function's arguments at the time the function is deferred, so the current time gets captured at the point of the defer. When the function containing the defer returns, the deferred from function runs, computes the elapsed time as a time.Duration, and prints it with standard formatting, which adds a nicely scaled unit suffix.

package main
 
import (
"fmt"
"time"
)
 
func from(t0 time.Time) {
fmt.Println(time.Now().Sub(t0))
}
 
func empty() {
defer from(time.Now())
}
 
func count() {
defer from(time.Now())
for i := 0; i < 1e6; i++ {
}
}
 
func main() {
empty()
count()
}

Output:

2us
643us

Groovy[edit]

Translation of: Java

CPU Timing[edit]

import java.lang.management.ManagementFactory
import java.lang.management.ThreadMXBean
 
def threadMX = ManagementFactory.threadMXBean
assert threadMX.currentThreadCpuTimeSupported
threadMX.threadCpuTimeEnabled = true
 
def clockCpuTime = { Closure c ->
def start = threadMX.currentThreadCpuTime
c.call()
(threadMX.currentThreadCpuTime - start)/1000000
}

Wall Clock Timing[edit]

def clockRealTime = { Closure c ->
def start = System.currentTimeMillis()
c.call()
System.currentTimeMillis() - start
}

Test:

def countTo = { Long n ->
long i = 0; while(i < n) { i += 1L }
}
 
["CPU time":clockCpuTime, "wall clock time":clockRealTime].each { measurementType, timer ->
println '\n'
[100000000L, 1000000000L].each { testSize ->
def measuredTime = timer(countTo.curry(testSize))
println "Counting to ${testSize} takes ${measuredTime}ms of ${measurementType}"
}
}

Output:

Counting to 100000000 takes 23150.5484ms of CPU time
Counting to 1000000000 takes 233861.0991ms of CPU time


Counting to 100000000 takes 24314ms of wall clock time
Counting to 1000000000 takes 249005ms of wall clock time

Haskell[edit]

import System.CPUTime (getCPUTime)
 
-- We assume the function we are timing is an IO monad computation
timeIt :: (Fractional c) => (a -> IO b) -> a -> IO c
timeIt action arg = do
startTime <- getCPUTime
action arg
finishTime <- getCPUTime
return $ fromIntegral (finishTime - startTime) / 1000000000000
 
-- Version for use with evaluating regular non-monadic functions
timeIt_ :: (Fractional c) => (a -> b) -> a -> IO c
timeIt_ f = timeIt ((`seq` return ()) . f)

Example[edit]

*Main> :m + Text.Printf Data.List
*Main Data.List Text.Printf> timeIt' id 4 >>= printf "Identity(4) takes %f seconds.\n"
Identity(4) takes 0.0 seconds.
*Main Data.List Text.Printf> timeIt' (\x -> foldl' (+) x [1..1000000]) 4 >>= printf "Sum(4) takes %f seconds.\n"
Sum(4) takes 0.248015 seconds.

HicEst[edit]

t_start = TIME()    ! returns seconds since midnight
SYSTEM(WAIT = 1234) ! wait 1234 milliseconds
t_end = TIME()
 
WRITE(StatusBar) t_end - t_start, " seconds"

Icon and Unicon[edit]

The function 'timef' takes as argument a procedure name and collects performance and timing information including run time (in milliseconds), garbage collection, and memory usage by region.

procedure timef(f)                               #: time a function f
local gcol,alloc,used,size,runtime,header,x,i
 
title := ["","total","static","string","block"] # headings
collect() # start with collected memory (before baseline)
every put(gcol := [], -&collections) # baseline collections count
every put(alloc := [], -&allocated) # . total allocated space by region
every put(used := [], -&storage) # . currently used space by region - no total
every put(size := [], -&regions) # . current size of regions - no total
 
write("Performance and Timing measurement for ",image(f),":")
runtime := &time # base time
f()
write("Execution time=",&time-runtime," ms.")
 
every (i := 0, x := &collections) do gcol[i +:= 1] +:= x
every (i := 0, x := &allocated ) do alloc[i +:= 1] +:= x
every (i := 0, x := &storage ) do used[i +:= 1] +:= x
every (i := 0, x := &regions ) do size[i +:= 1] +:= x
 
push(gcol,"garbage collections:")
push(alloc,"memory allocated:")
push(used,"N/A","currently used:")
push(size,"N/A","current size:")
 
write("Memory Region and Garbage Collection Summary (delta):")
every (i := 0) <:= *!(title|gcol|alloc|used|size)
every x := (title|gcol|alloc|used|size) do {
f := left
every writes(f(!x,i + 3)) do f := right
write()
}
write("Note: static region values should be zero and may not be meaningful.")
return
end
Sample usage:
procedure main()
timef(perfectnumbers)
end
 
procedure perfectnumbers()
...

Sample output (from the Perfect Numbers task):

Performance and Timing measurement for procedure perfectnumbers:
Perfect numbers from 1 to 10000:
6
28
496
8128
Done.
Execution time=416 ms.
Memory Region and Garbage Collection Summary (delta):
                                         total                 static                 string                  block
garbage collections:                         2                      0                      0                      2
memory allocated:                      1247012                      0                     24                1246988
currently used:                            N/A                      0                      0                 248040
current size:                              N/A                      0                      0                      0
Note: static region values should be zero and may not be meaningful.

Ioke[edit]

use("benchmark")
 
func = method((1..50000) reduce(+))
 
Benchmark report(1, 1, func)

J[edit]

Time and space requirements are tested using verbs obtained through the Foreign conjunction (!:). 6!:2 returns time required for execution, in floating-point measurement of seconds. 7!:2 returns a measurement of space required to execute. Both receive as input a sentence for execution. The verb timespacex combines these and is available in the standard library.
When the Memoize feature or similar techniques are used, execution time and space can both be affected by prior calculations.

Example[edit]

   (6!:2 , 7!:2) '|: 50 50 50 $ i. 50^3'
0.00488008 3.14829e6
timespacex '|: 50 50 50 $ i. 50^3'
0.00388519 3.14829e6

Java[edit]

Works with: Java version 1.5+
import java.lang.management.ManagementFactory;
import java.lang.management.ThreadMXBean;
 
public class TimeIt {
public static void main(String[] args) {
final ThreadMXBean threadMX = ManagementFactory.getThreadMXBean();
assert threadMX.isCurrentThreadCpuTimeSupported();
threadMX.setThreadCpuTimeEnabled(true);
 
long start, end;
start = threadMX.getCurrentThreadCpuTime();
countTo(100000000);
end = threadMX.getCurrentThreadCpuTime();
System.out.println("Counting to 100000000 takes "+(end-start)/1000000+"ms");
start = threadMX.getCurrentThreadCpuTime();
countTo(1000000000L);
end = threadMX.getCurrentThreadCpuTime();
System.out.println("Counting to 1000000000 takes "+(end-start)/1000000+"ms");
 
}
 
public static void countTo(long x){
System.out.println("Counting...");
for(long i=0;i<x;i++);
System.out.println("Done!");
}
}

Measures real time rather than CPU time:

Works with: Java version (all versions)
	public static void main(String[] args){
long start, end;
start = System.currentTimeMillis();
countTo(100000000);
end = System.currentTimeMillis();
System.out.println("Counting to 100000000 takes "+(end-start)+"ms");
start = System.currentTimeMillis();
countTo(1000000000L);
end = System.currentTimeMillis();
System.out.println("Counting to 1000000000 takes "+(end-start)+"ms");
 
}

Output:

Counting...
Done!
Counting to 100000000 takes 370ms
Counting...
Done!
Counting to 1000000000 takes 3391ms

Kotlin[edit]

Translation of: Java
// version 1.1.2
// need to enable runtime assertions with JVM -ea option
 
import java.lang.management.ManagementFactory
import java.lang.management.ThreadMXBean
 
fun countTo(x: Int) {
println("Counting...");
(1..x).forEach {}
println("Done!")
}
 
fun main(args: Array<String>) {
val counts = intArrayOf(100_000_000, 1_000_000_000)
val threadMX = ManagementFactory.getThreadMXBean()
assert(threadMX.isCurrentThreadCpuTimeSupported)
threadMX.isThreadCpuTimeEnabled = true
for (count in counts) {
val start = threadMX.currentThreadCpuTime
countTo(count)
val end = threadMX.currentThreadCpuTime
println("Counting to $count takes ${(end-start)/1000000}ms")
}
}

This is a typical result (sometimes the second figure is only about 1400ms - no idea why)

Output:
Counting...
Done!
Counting to 100000000 takes 179ms
Counting...
Done!
Counting to 1000000000 takes 3527ms

Lasso[edit]

local(start = micros)
loop(100000) => {
'nothing is outout because no autocollect'
}
'time for 100,000 loop repititions: '+(micros - #start)+' microseconds'

Lingo[edit]

on testFunc ()
repeat with i = 1 to 1000000
x = sqrt(log(i))
end repeat
end
ms = _system.milliseconds
testFunc()
ms = _system.milliseconds - ms
put "Execution time in ms:" && ms
-- "Execution time in ms: 983"

[edit]

Works with: UCB Logo
on a Unix system

This is not an ideal method; Logo does not expose a timer (except for the WAIT command) so we use the Unix "date" command to get a second timer.

to time
output first first shell "|date +%s|
end
to elapsed :block
localmake "start time
run :block
(print time - :start [seconds elapsed])
end
 
elapsed [wait 300]  ; 5 seconds elapsed

Lua[edit]

function Test_Function()
for i = 1, 10000000 do
local s = math.log( i )
s = math.sqrt( s )
end
end
 
t1 = os.clock()
Test_Function()
t2 = os.clock()
 
print( os.difftime( t2, t1 ) )

Maple[edit]

The built-in command CodeTools:-Usage can compute the "real" time for the length of the computation or the "cpu" time for the computation. The following examples find the real time and cpu time for computing the integer factors for 32!+1.

CodeTools:-Usage(ifactor(32!+1), output = realtime, quiet);
CodeTools:-Usage(ifactor(32!+1), output = cputime, quiet);

Mathematica[edit]

AbsoluteTiming[x];

where x is an operation. Example calculating a million digits of Sqrt[3]:

AbsoluteTiming[N[Sqrt[3], 10^6]]

gives:

{0.000657, 1.7320508075688772935274463......}

First elements if the time in seconds, second elements if the result from the operation. Note that I truncated the result.

Maxima[edit]

f(n) := if n < 2 then n else f(n - 1) + f(n - 2)$
 
/* First solution, call the time function with an output line number, it gives the time taken to compute that line.
Here it's assumed to be %o2 */
f(24);
46368
 
time(%o2);
[0.99]
 
/* Second solution, change a system flag to print timings for all following lines */
showtime: true$
 
f(24);
Evaluation took 0.9400 seconds (0.9400 elapsed)
46368

Nim[edit]

import times, os
 
proc doWork(x) =
var n = x
for i in 0..10000000:
n += i
echo n
 
template time(s: stmt): expr =
let t0 = cpuTime()
s
cpuTime() - t0
 
echo time(doWork(100))

Output:

2.2000000000000000e-01

OCaml[edit]

let time_it action arg =
let start_time = Sys.time () in
ignore (action arg);
let finish_time = Sys.time () in
finish_time -. start_time

Example[edit]

# Printf.printf "Identity(4) takes %f seconds.\n" (time_it (fun x -> x) 4);;
Identity(4) takes 0.000000 seconds.
- : unit = ()
# let sum x = let num = ref x in for i = 0 to 999999 do num := !num + i done; !num;;
val sum : int -> int = <fun>
# Printf.printf "Sum(4) takes %f seconds.\n" (time_it sum 4);;
Sum(4) takes 0.084005 seconds.
- : unit = ()

Oforth[edit]

bench allows to calculate how long a runnable takes to execute.

Result is microseconds.

It uses difference between system time, not processing time.

Output:
>#[ 0 1000 seq apply(#+) ] bench .
267
500500 ok

Oz[edit]

declare
%% returns milliseconds
fun {TimeIt Proc}
Before = {Now}
in
{Proc}
{Now} - Before
end
 
fun {Now}
{Property.get 'time.total'}
end
in
{Show
{TimeIt
proc {$}
{FoldL {List.number 1 1000000 1} Number.'+' 4 _}
end}
}

PARI/GP[edit]

This version, by default, returns just the CPU time used by gp, not the delta of wall times. PARI can be compiled to use wall time if you prefer: configure with --time=ftime instead of --time= getrusage, --time=clock_gettime, or --time=times. See Appendix A, section 2.2 of the User's Guide to PARI/GP.

time(foo)={
foo();
gettime();
}

Alternate version:

Works with: PARI/GP version 2.6.2+
time(foo)={
my(start=getabstime());
foo();
getabstime()-start;
}

Perl[edit]

Example of using the built-in Benchmark core module - it compares two versions of recursive factorial functions:

use Benchmark;
use Memoize;
 
sub fac1 {
my $n = shift;
return $n == 0 ? 1 : $n * fac1($n - 1);
}
sub fac2 {
my $n = shift;
return $n == 0 ? 1 : $n * fac2($n - 1);
}
memoize('fac2');
 
my $result = timethese(100000, {
'fac1' => sub { fac1(50) },
'fac2' => sub { fac2(50) },
});
Benchmark::cmpthese($result);

Output:

Benchmark: timing 100000 iterations of fac1, fac2...
      fac1:  6 wallclock secs ( 5.45 usr +  0.00 sys =  5.45 CPU) @ 18348.62/s (n=100000)
      fac2:  1 wallclock secs ( 0.84 usr +  0.00 sys =  0.84 CPU) @ 119047.62/s (n=100000)
         Rate fac1 fac2
fac1  18349/s   -- -85%
fac2 119048/s 549%   --

Example without using Benchmark:

sub cpu_time {
my ($user,$system,$cuser,$csystem) = times;
$user + $system
}
 
sub time_it {
my $action = shift;
my $startTime = cpu_time();
$action->(@_);
my $finishTime = cpu_time();
$finishTime - $startTime
}
 
printf "Identity(4) takes %f seconds.\n", time_it(sub {@_}, 4);
# outputs "Identity(4) takes 0.000000 seconds."
 
sub sum {
my $x = shift;
foreach (0 .. 999999) {
$x += $_;
}
$x
}
 
printf "Sum(4) takes %f seconds.\n", time_it(\&sum, 4);
# outputs "Sum(4) takes 0.280000 seconds."

Perl 6[edit]

Follows modern trend toward measuring wall-clock time, since CPU time is becoming rather ill-defined in the age of multicore, and doesn't reflect IO overhead in any case.

my $start = now;
(^100000).pick(1000);
say now - $start;
Output:
0.02301709

Phix[edit]

Measures wall-clock time. On Windows the resolution is about 15ms.

atom t0 = time()
some_procedure()
printf(1,"%3.2fs.\n",time()-t0)

PicoLisp[edit]

There is a built-in function 'bench' for that. However, it measures wall-clock time, because for practical purposes the real time needed by a task (including I/O and communication) is more meaningful. There is another function, 'tick', which also measures user time, and is used by the profiling tools.

: (bench (do 1000000 (* 3 4)))
0.080 sec
-> 12

PL/I[edit]

declare (start_time, finish_time) float (18);
 
start_time = secs();
 
do i = 1 to 10000000;
/* something to be repeated goes here. */
end;
finish_time = secs();
 
put skip edit ('elapsed time=', finish_time - start_time, ' seconds')
(A, F(10,3), A);
/* gives the result to thousandths of a second. */
 
/* Note: using the SECS function takes into account the clock */
/* going past midnight. */

PowerShell[edit]

 
function fun($n){
$res = 0
if($n -gt 0) {
1..$n | foreach{
$a, $b = $_, ($n+$_)
$res += $a + $b
}
 
}
$res
}
"$((Measure-Command {fun 10000}).TotalSeconds) Seconds"
 

Output:

0.820712 Seconds


PureBasic[edit]

Built in timer[edit]

This version uses the built in timer, on Windows it has an accuracy of ~10-15 msec.

Procedure Foo(Limit)
Protected i, palindromic, String$
For i=0 To Limit
String$=Str(i)
If String$=ReverseString(String$)
palindromic+1
EndIf
Next
ProcedureReturn palindromic
EndProcedure
 
If OpenConsole()
Define Start, Stop, cnt
PrintN("Starting timing of a calculation,")
PrintN("for this we test how many of 0-1000000 are palindromic.")
Start=ElapsedMilliseconds()
cnt=Foo(1000000)
Stop=ElapsedMilliseconds()
PrintN("The function need "+Str(stop-Start)+" msec,")
PrintN("and "+Str(cnt)+" are palindromic.")
Print("Press ENTER to exit."): Input()
EndIf
Starting timing of a calculation,
for this we test how many of 0-1000000 are palindromic.
The function need 577 msec,
and 1999 are palindromic.
Press ENTER to exit.

Hi-res version[edit]

Library: Droopy

This version uses a hi-res timer, but it is Windows only.

If OpenConsole()
Define Timed.f, cnt
PrintN("Starting timing of a calculation,")
PrintN("for this we test how many of 0-1000000 are palindromic.")
; Dependent on Droopy-library
If MeasureHiResIntervalStart()
; Same Foo() as above...
cnt=Foo(1000000)
Timed=MeasureHiResIntervalStop()
EndIf
PrintN("The function need "+StrF(Timed*1000,3)+" msec,")
PrintN("and "+Str(cnt)+" are palindromic.")
Print("Press ENTER to exit."): Input()
EndIf
Starting timing of a calculation,
for this we test how many of 0-1000000 are palindromic.
The function need 604.341 msec,
and 1999 are palindromic.
Press ENTER to exit.

This version still relies on the Windows API but does not make use of any additional libraries.

Procedure.f ticksHQ(reportIfPresent = #False)
Static maxfreq.q
Protected T.q
If reportIfPresent Or maxfreq = 0
QueryPerformanceFrequency_(@maxfreq)
If maxfreq
ProcedureReturn 1.0
Else
ProcedureReturn 0
EndIf
EndIf
QueryPerformanceCounter_(@T)
ProcedureReturn T / maxfreq ;Result is in milliseconds
EndProcedure
 
If OpenConsole()
Define timed.f, cnt
PrintN("Starting timing of a calculation,")
PrintN("for this we test how many of 0-1000000 are palindromic.")
; Dependent on Windows API
If ticksHQ(#True)
timed = ticksHQ() ;start time
; Same Foo() as above...
cnt = Foo(1000000)
timed = ticksHQ() - timed ;difference
EndIf
PrintN("The function need " + StrF(timed * 1000, 3) + " msec,")
PrintN("and " + Str(cnt) + " are palindromic.")
Print("Press ENTER to exit."): Input()
EndIf

Sample output:

Starting timing of a calculation,
for this we test how many of 0-1000000 are palindromic.
The function need 174.811 msec,
and 1999 are palindromic.

Python[edit]

Given function and arguments return a time (in microseconds) it takes to make the call.

Note: There is an overhead in executing a function that does nothing.

import sys, timeit
def usec(function, arguments):
modname, funcname = __name__, function.__name__
timer = timeit.Timer(stmt='%(funcname)s(*args)' % vars(),
setup='from %(modname)s import %(funcname)s; args=%(arguments)r' % vars())
try:
t, N = 0, 1
while t < 0.2:
t = min(timer.repeat(repeat=3, number=N))
N *= 10
microseconds = round(10000000 * t / N, 1) # per loop
return microseconds
except:
timer.print_exc(file=sys.stderr)
raise
 
def nothing(): pass
def identity(x): return x

Example[edit]

>>> print usec(nothing, [])
1.7
>>> print usec(identity, [1])
2.2
>>> print usec(pow, (2, 100))
3.3
>>> print [usec(qsort, (range(n),)) for n in range(10)]
[2.7, 2.8, 31.4, 38.1, 58.0, 76.2, 100.5, 130.0, 149.3, 180.0]

using qsort() from Quicksort. Timings show that the implementation of qsort() has quadratic dependence on sequence length N for already sorted sequences (instead of O(N*log(N)) in average).

R[edit]

R has a built-in function, system.time, to calculate this.

# A task
foo <- function()
{
for(i in 1:10)
{
mat <- matrix(rnorm(1e6), nrow=1e3)
mat^-0.5
}
}
# Time the task
timer <- system.time(foo())
# Extract the processing time
timer["user.self"]

For a breakdown of processing time by function, there is Rprof.

Rprof()
foo()
Rprof(NULL)
summaryRprof()

Racket[edit]

 
#lang racket
(define (fact n) (if (zero? n) 1 (* n (fact (sub1 n)))))
(time (fact 5000))
 

Raven[edit]

define doId use $x
$x dup * $x /
 
define doPower use $v, $p
$v $p pow
 
define doSort
group
20000 each choose
list sort reverse
 
define timeFunc use $fName
time as $t1
$fName "" prefer call
time as $t2
$fName $t2 $t1 -"%.4g secs for %s\n" print
 
"NULL" timeFunc
42 "doId" timeFunc
12 2 "doPower" timeFunc
"doSort" timeFunc
Output:
2.193e-05 secs for NULL
2.003e-05 secs for doId
4.601e-05 secs for doPower
3.028 secs for doSort

Retro[edit]

Retro has a time function returning the current time in seconds. This can be used to build a simple timing function:

: .runtime ( a- ) time [ do time ] dip - "\n%d\n" puts ;
 
: test 20000 [ putn space ] iterd ;
&test .runtime

Finer measurements are not possible with the standard implementation.

REXX[edit]

elapsed time version[edit]

REXX doesn't have a language feature for obtaining true CPU time (except under
IBM mainframes which have commands that can retrieve such times), but it does
have a built-in function for elapsed time(s).

The main reason for the true CPU time omission is that REXX was developed under VM/CMS and
there's a way to easily query the host (VM/CP) to indicate how much   true   CPU time was used by
(normally) your own userID.  The result can then be placed into a REXX variable (as an option).

/*REXX program displays the elapsed time for a REXX function (or subroutine). */
arg reps . /*obtain an optional argument from C.L.*/
if reps=='' then reps=100000 /*Not specified? No, then use default.*/
call time 'Reset' /*only the 1st character is examined. */
junk = silly(reps) /*invoke the SILLY function (below). */
/*───► CALL SILLY REPS also works.*/
 
/* The E is for elapsed time.*/
/* │ ─ */
/* ┌────◄───┘ */
/* │ */
/* ↓ */
say 'function SILLY took' format(time("E"),,2) 'seconds for' reps "iterations."
/* ↑ */
/* │ */
/* ┌────────►───────┘ */
/* │ */
/* The above 2 for the FORMAT function displays the time with*/
/* two decimal digits (rounded) past the decimal point). Using */
/* a 0 (zero) would round the time to whole seconds. */
exit /*stick a fork in it, we're all done. */
/*────────────────────────────────────────────────────────────────────────────*/
silly: procedure /*chew up some CPU time doing some silly stuff.*/
do j=1 for arg(1) /*wash, apply, lather, rinse, repeat. ··· */
@.j=random() date() time() digits() fuzz() form() xrange() queued()
end /*j*/
return j-1

output   when using a personal computer built in the 20th century:

function SILLY took 3.54 seconds for 100000 iterations.

output   when using a personal computer built in the 21st century:

function SILLY took 0.44 seconds for 100000 iterations.

output   when using an IBM mainframe with MVS/TSO:

function SILLY took 0.69 seconds for 100000 iterations. 

CPU time used version[edit]

This version only works with Regina REXX as the   J   option is a Regina extension.

Since the   silly   function (by far) consumes the bulk of the CPU time of the REXX program, what is
being measured is essentially the same as the wall clock time (duration) of the function execution;   the
overhead of the invocation is minimal compared to the overall time used.

/*REXX program displays the elapsed time for a REXX function (or subroutine). */
arg reps . /*obtain an optional argument from C.L.*/
if reps=='' then reps=100000 /*Not specified? No, then use default.*/
call time 'Reset' /*only the 1st character is examined. */
junk = silly(reps) /*invoke the SILLY function (below). */
/*───► CALL SILLY REPS also works.*/
 
/* The J is for the CPU time used */
/* │ by the REXX program since */
/* ┌───────┘ since the time was RESET. */
/* │ This is a Regina extension.*/
/* ↓ */
say 'function SILLY took' format(time("J"),,2) 'seconds for' reps "iterations."
/* ↑ */
/* │ */
/* ┌────────►───────┘ */
/* │ */
/* The above 2 for the FORMAT function displays the time with*/
/* two decimal digits (rounded) past the decimal point). Using */
/* a 0 (zero) would round the time to whole seconds. */
exit /*stick a fork in it, we're all done. */
/*────────────────────────────────────────────────────────────────────────────*/
silly: procedure /*chew up some CPU time doing some silly stuff.*/
do j=1 for arg(1) /*wash, apply, lather, rinse, repeat. ··· */
@.j=random() date() time() digits() fuzz() form() xrange() queued()
end /*j*/
return j-1

output   is essentially identical to the previous examples.

Ring[edit]

 
beginTime = TimeList()[13]
for n = 1 to 10000000
n = n + 1
next
endTime = TimeList()[13]
elapsedTime = endTime - beginTime
see "Elapsed time = " + elapsedTime + nl
 

Ruby[edit]

Ruby's Benchmark module provides a way to generate nice reports (numbers are in seconds):

require 'benchmark'
 
Benchmark.bm(8) do |x|
x.report("nothing:") { }
x.report("sum:") { (1..1_000_000).inject(4) {|sum, x| sum + x} }
end

Output:

              user     system      total        real
nothing:  0.000000   0.000000   0.000000 (  0.000014)
sum:      2.700000   0.400000   3.100000 (  3.258348)

You can get the total time as a number for later processing like this:

Benchmark.measure { whatever }.total

Scala[edit]

Define a time function that returns the elapsed time (in ms) to execute a block of code.

 
def time(f: => Unit)={
val s = System.currentTimeMillis
f
System.currentTimeMillis - s
}
 

Can be called with a code block:

 
println(time {
for(i <- 1 to 10000000) {}
})
 

Or with a function:

 
def count(i:Int) = for(j <- 1 to i){}
 
println(time (count(10000000)))
 

Scheme[edit]

(time (some-function))

Seed7[edit]

$ include "seed7_05.s7i";
include "time.s7i";
include "duration.s7i";
 
const func integer: identity (in integer: x) is
return x;
 
const func integer: sum (in integer: num) is func
result
var integer: result is 0;
local
var integer: number is 0;
begin
result := num;
for number range 1 to 1000000 do
result +:= number;
end for;
end func;
 
const func duration: timeIt (ref func integer: aFunction) is func
result
var duration: result is duration.value;
local
var time: before is time.value;
begin
before := time(NOW);
ignore(aFunction);
result := time(NOW) - before;
end func;
 
const proc: main is func
begin
writeln("Identity(4) takes " <& timeIt(identity(4)));
writeln("Sum(4) takes " <& timeIt(sum(4)));
end func;
Output:
of interpreted program:
Identity(4) takes 0-00-00 00:00:00.000163
Sum(4)      takes 0-00-00 00:00:00.131823
Output:
of compiled program (optimized with -O2):
Identity(4) takes 0-00-00 00:00:00.000072
Sum(4)      takes 0-00-00 00:00:00.000857

Sidef[edit]

var benchmark = frequire('Benchmark')
 
func fac_rec(n) {
n == 0 ? 1 : (n * __FUNC__(n - 1))
}
 
func fac_iter(n) {
var prod = 1
n.times { |i|
prod *= i
}
prod
}
 
var result = benchmark.timethese(-3, Hash(
'fac_rec' => { fac_rec(20) },
'fac_iter' => { fac_iter(20) },
))
 
benchmark.cmpthese(result)
Output:
Benchmark: running fac_iter, fac_rec for at least 3 CPU seconds...
  fac_iter:  3 wallclock secs ( 3.23 usr +  0.00 sys =  3.23 CPU) @ 7331.89/s (n=23682)
   fac_rec:  3 wallclock secs ( 3.19 usr +  0.00 sys =  3.19 CPU) @ 3551.72/s (n=11330)
           Rate  fac_rec fac_iter
fac_rec  3552/s       --     -52%
fac_iter 7332/s     106%       --

Slate[edit]

 
[inform: 2000 factorial] timeToRun.
 

Smalltalk[edit]

(Squeak/Pharo)

 
Time millisecondsToRun: [
Transcript show: 2000 factorial ].
 

Standard ML[edit]

fun time_it (action, arg) = let
val timer = Timer.startCPUTimer ()
val _ = action arg
val times = Timer.checkCPUTimer timer
in
Time.+ (#usr times, #sys times)
end

Example[edit]

- print ("Identity(4) takes " ^ Time.toString (time_it (fn x => x, 4)) ^ " seconds.\n");
Identity(4) takes 0.000 seconds.
val it = () : unit
- fun sum (x:IntInf.int) = let
    fun loop (i, sum) =
      if i >= 1000000 then sum
      else loop (i + 1, sum + i)
  in loop (0, x)
  end;
val sum = fn : IntInf.int -> IntInf.int
- print ("Sum(4) takes " ^ Time.toString (time_it (sum, 4)) ^ " seconds.\n");
Sum(4) takes 0.220 seconds.
val it = () : unit

Stata[edit]

Stata can track up to 100 timers. See timer in Stata help.

program timer_test
timer clear 1
timer on 1
sleep `0'
timer off 1
timer list 1
end
 
. timer_test 1000
1: 1.01 / 1 = 1.0140

Tcl[edit]

The Tcl time command returns the real time elapsed averaged over a number of iterations.

proc sum_n {n} {
for {set i 1; set sum 0.0} {$i <= $n} {incr i} {set sum [expr {$sum + $i}]}
return [expr {wide($sum)}]
}
 
puts [time {sum_n 1e6} 100]
puts [time {} 100]
Output:
163551.0 microseconds per iteration
0.2 microseconds per iteration

TorqueScript[edit]

Greek2me 02:16, 19 June 2012 (UTC)

Returns average time elapsed from many iterations.

 
function benchmark(%times,%function,%a,%b,%c,%d,%e,%f,%g,%h,%i,%j,%k,%l,%m,%n,%o)
{
if(!isFunction(%function))
{
warn("BENCHMARKING RESULT FOR" SPC %function @ ":" NL "Function does not exist.");
return -1;
}
 
%start = getRealTime();
 
for(%i=0; %i < %times; %i++)
{
call(%function,%a,%b,%c,%d,%e,%f,%g,%h,%i,%j,%k,%l,%m,%n,%o);
}
 
%end = getRealTime();
 
%result = (%end-%start) / %times;
 
warn("BENCHMARKING RESULT FOR" SPC %function @ ":" NL %result);
 
return %result;
}
 
Example:
 
function exampleFunction(%var1,%var2)
{
//put stuff here
}
 
benchmark(500,"exampleFunction","blah","variables");
 
==> BENCHMARKING RESULT FOR exampleFunction:
==> 13.257
 

TUSCRIPT[edit]

 
$$ MODE TUSCRIPT
SECTION test
LOOP n=1,999999
rest=MOD (n,1000)
IF (rest==0) Print n
ENDLOOP
ENDSECTION
time_beg=TIME ()
DO test
time_end=TIME ()
interval=TIME_INTERVAL (seconds,time_beg,time_end)
PRINT "'test' start at ",time_beg
PRINT "'test' ends at ",time_end
PRINT "'test' takes ",interval," seconds"
 
Output:
'test' start at 2011-01-15 14:38:22
'test' ends  at 2011-01-15 14:38:31
'test' takes 9 seconds

UNIX Shell[edit]

$ time sleep 1
real    0m1.074s
user    0m0.001s
sys     0m0.006s

Wart[edit]

time 1+1
30000/1000000 # in microseconds
=> 2

XPL0[edit]

This works fine under pure DOS but has problems under Windows. Windows can execute other processes, although it could be argued that this should be included as part of the total time to accomplish the task at hand. DOS does go off to service a timer interrupt, but it's usually very fast, although beware of TSRs that hook this interrupt handler.

There's a more serious problem with the GetTime intrinsic under Windows XP. GetTime provides microsecond resolution by combining the BIOS timer interrupt count at location 046C with the count in the 8254 chip (or its equivalent). Unfortunately, Windows virtualizes the 8254 and thus the two values can be out of sync.

include c:\cxpl\codes;
int T0, T1, I;
[T0:= GetTime;
for I:= 1, 1_000_000 do [];
T1:= GetTime;
IntOut(0, T1-T0); Text(0, " microseconds^M^J");
]
Example output:
for a Duron 850 running DOS 5.0:
2354 microseconds

zkl[edit]

In order to be as OS independent as possible, only system time is available.

t:=Time.Clock.time; Atomic.sleep(3); (Time.Clock.time - t).println();
Output:
3