90

So, Unix has a time command that lets users time their code/other things. I was wondering if the Windows command line has anything similar.

Also, I asked a previous question regarding the Linux command line here. Can we do the same for Windows? If so, how?

4
  • 2
    Windows has the standard cmd.exe but if you want something closer to the linux version get the powershell, its way better.
    – Guillermo
    Jan 1, 2011 at 22:53
  • I searched for "command time for windows" on google on the first result gives: http://stackoverflow.com/questions/673523/how-to-measure-execution-time-of-command-in-windows-command-line Jan 1, 2011 at 22:55
  • I'm on Windows 7 and I just tried the solution posted above. I get the following error: Unable to query system performance data (c0000004). I googled it and someone else had the exact same problem, but the forum suggests no solution. Thanks for the suggestion anyway. Can someone suggest something for the other part? Jan 1, 2011 at 23:10
  • @eff, timeit.exe is for server 2003 and XP AFAIK, I don't think its compatible with 7.
    – John T
    Jan 1, 2011 at 23:39

12 Answers 12

65

Use Powershell

Measure-Command {start-process whateveryouwantexecute -Wait}

Edited to your need @efficiencylsBliss:

Measure-Command {start-process java -argumentlist "whateverargumentisneeded" -wait}
12
  • Here's what I tried: Measure-Command {java test <inputfile> -Wait}. I got a list of time-related statistics, but not the output from the code. Am I doing something wrong? Jan 2, 2011 at 0:50
  • @efficiency: You forgot the start-process command. Jan 2, 2011 at 1:40
  • Start-Process : A positional parameter cannot be found that accepts argument '.\6-8.txt'. At line:1 char:31 + Measure-Command {start-process <<<< java .\dancebattle .\6-8.txt -wait} + CategoryInfo : InvalidArgument: (:) [Start-Process], ParameterBindingException + FullyQualifiedErrorId : PositionalParameterNotFound,Microsoft.PowerShell.Commands.StartProcessCommand` Jan 2, 2011 at 15:01
  • 1
    I'm trying to measure the time it takes to run a Python script using Measure-Command {start-process \Python27\python test.py -Wait}. This opens up a new cmd window to run the process, but then closes the window when it's done running. I'd like to see the output of the script as well, so how can I keep the window open? Apr 10, 2013 at 15:34
  • 2
    @JohnPeterThompsonGarcés use the -NoNewWindow parameter of the start-process cmdlet
    – mjsr
    Apr 10, 2013 at 16:29
24

I'm using Win XP, for some reason, timeit.exe is not working for me. I found another alternative: ptime:

ptime 1.0 - Accurately measure program execution time

ptime will run any specified command and parameters, and measure the execution time (run time) in seconds, accurate to 5 millisecond or better. It is an automatic process timer, or program timer used for benchmark purposes.

3
  • 1
    ptime have one small bug. ptime always return 0 as error level, even if "child" program exit with error Sep 16, 2015 at 8:23
  • Super simple and accurate output.
    – janpio
    Aug 20, 2018 at 8:50
  • Seems to work fine in Win10.
    – mivk
    Sep 16, 2018 at 12:30
21

You can cheat a little with a batch script...

@echo off
echo %time% < nul
cmd /c %1
echo %time% < nul

Then run your program as an argument to this script...

timer myprogram.exe

and for arguments...

timer "myprogram.exe -sw1 -sw2"

example output:

17:59:20.02
some text
17:59:20.03

place the batch script somewhere in your PATH variable, e.g. C:\Windows\System32 and name it timer.cmd. Of course there is a small performance hit of forking a second cmd instance, although very minimal.

4
  • that prompt wouldn't work, @echo off echo %time% < nul cmd /c %1 echo %time% < nul you left out the closing % on the environment variable(?)
    – user61885
    Jan 7, 2011 at 18:07
  • There is no closing % for command line parameters like %1. Is that what you meant? Apr 30, 2011 at 11:42
  • 4
    Why would you redirect nul into echo? echo doesn't ever read input.
    – Joey
    Jan 4, 2014 at 11:28
  • 1
    You can change cmd /c %1 to cmd /c %*, so that you can save quotation mark for command arguments Dec 3, 2017 at 9:23
7

For ease of use, here is the chocolatey package: https://chocolatey.org/packages/ptime C:/> choco install ptime

The advantage if ptime is that it acts like the unix version and yields the console output, which Measure-Command { XXX } does not (or at least I don't know how to do that).

6

There is no direct equivalent to Unix time on Windows.

The University of Georgia have a brief list of Windows commands for Unix users

I find the older Windows command prompt and .bat scripting is rather limited compared to Unix shells but there are some facilities for looping over files etc. CommandWindows.com has some tips

You could either install bash on Windows (e.g. by installing CygWin) or learn Windows Powershell (which I am assuming has a means of doing something equivalent).

0
5

Some coffee helped me come up with this:

function time { $Command = "$args"; Measure-Command { Invoke-Expression $Command 2>&1 | out-default} }

And if you want it to output nothing, just replace with out-null:

function timequiet { $Command = "$args"; Measure-Command { Invoke-Expression $Command 2>&1 | out-null} }

You use it like this:

PS C:\> time sleep 5


Days              : 0
Hours             : 0
Minutes           : 0
Seconds           : 4
Milliseconds      : 990
Ticks             : 49906722
TotalDays         : 5,77624097222222E-05
TotalHours        : 0,00138629783333333
TotalMinutes      : 0,08317787
TotalSeconds      : 4,9906722
TotalMilliseconds : 4990,6722



PS C:\>
3

gnomon is a nice solution if you don't only need the total run time of a command, but also line for line measurements:

A command line utility to prepend timestamp information to the standard output of another command. Useful for long-running processes where you'd like a historical record of what's taking so long.

Installed by running npm install -g gnomon, then just use it via command | gnomon.

2

The output for your code can be piped to a file: java test <inputfile> | Out-File d:\a.txt

For measuring how long it takes you have to encapsulate it in Measure-Commmand:

Measure-Commmand {java test <inputfile> | Out-File d:\a.txt}

2

If you try to use PowerShell with Measure-Command be aware that there may be some unexpected gotchas. My command writes binary data to a file using > redirection but PowerShell added a BOM to the beginning of the file and a CRLF line break after every write!

1

You can write C++ code using Windows API to create a utility tool for yourself.

Possible reasons to do so:

  • You don't want to use PowerShell.
  • You want more control of the time program. You may consider falling back to cmd /c <COMMAND> if <COMMAND> can only be interpreted by cmd.exe.
  • Normally, utility tools (e.g. ptime and MSYS2 time) take the process creation time into account. But Measure-Command in PowerShell does not. To get a closer estimation, you can record start time after the creating subprocess and before waiting for it. If you do want to include process creation time, just move the line where the start time is recorded.

Code:

#include <iostream>
#include <chrono>
#include <cstdlib>
#include <process.h>

using namespace std::chrono;

int main(int argc, char **argv) {
    if (argc < 2) {
        fprintf(stderr, "** Error: no command provided\n");
        exit(1);
    }
    
    printf("Running ");
    for (int i = 1; i < argc; ++i)
        printf("[%s] ", argv[i]);
    printf("\n");

    auto handle = _spawnvp(_P_NOWAIT, argv[1], &argv[1]);
    if (handle < 0) {
        perror("_spawnv failed");
        exit(1);
    }
    auto start_time = high_resolution_clock::now();
    int status;
    if (_cwait(&status, handle, _WAIT_CHILD) == -1) {
        perror("_cwait failed");
        exit(1);
    }

    auto end_time = high_resolution_clock::now();
    auto duration = duration_cast<milliseconds>(end_time - start_time);
    printf("duration: %lld ms\n", duration.count());
}

Assume the utility is mtime. Run mtime mtime in cmd:

cmd> mtime mtime
Running [mtime] 
** Error: no command provided
duration: 5 ms

The first mtime measures the running time of the second mtime, which fails fast (and can be considered as a "Hello World" program). Result should be 5 ~ 7 ms, and is so close to Measure-Command's estimation:

PowerShell> measure-command{.\mtime|Out-Default}
** Error: no command provided


Days              : 0
Hours             : 0
Minutes           : 0
Seconds           : 0
Milliseconds      : 6
Ticks             : 64007
TotalDays         : 7.40821759259259E-08
TotalHours        : 1.77797222222222E-06
TotalMinutes      : 0.000106678333333333
TotalSeconds      : 0.0064007
TotalMilliseconds : 6.4007

If you count process creation time, the result should be about 11 ms. (Process creation is much slower on Windows than on Linux.)

Caveats:

  • Do not pass _P_WAIT to _spawnvp. That way, when the subprocess exits with a non-zero code, your measuring program will fail as well (because it cannot tell whether process creation fails or subprocess exits abnormally).
  • Use cl.exe or clang++.exe to compile. Do not use g++.exe, because it cannot optimize Windows API as well as the other two. (My g++ version is g++ (Rev1, Built by MSYS2 project) 11.3.0, and clang++ version is clang version 14.0.0; Target: x86_64-pc-windows-msvc)
  • In PowerShell, measure-command{<COMMAND>|Out-Default} takes longer if <COMMAND> can only be resolved in PATH and your PATH is long (for my laptop it takes 14 ms for a "Hello World" exe at the bottom of PATH). In cmd, executable files are cached, so consecutive same commands run faster even if full path is not specified.

In my test, the program was compiled with no optimization. If you turn it on, program should be a little bit faster.

0

There are a couple different options to get a 'time' command. My preference is to just install Cygwin (which comes with a UNIX-like time command).

Alternatively, you can write a script and add it to your path (so that you can execute it without specifying the entire path).

If you have Powershell available, try this script (works when calling files--'.exe',etc.):

$start = get-date
if ($args.length -gt 1) {
start-process $args[0] $args[1..$args.length] -workingdirectory $pwd -nonewwindow -wait
} else {
start-process $args[0] -workingdirectory $pwd -nonewwindow -wait
}
$end = get-date
$elapsed = $end - $start
write-host $end-$start
# datetime format
write-host $elapsed
# easy-to-read format
echo $elapsed

Run the code with (for instance):

time.ps1 python program.py

Using Batch, I'd suggest either of the top answers from here (on Stackoverflow.com). Both just need to be copy-pasted. Note that if you use paxdiablo's solution, you should replace

ping -n 11 127.0.0.1 >nul: 2>nul: 

with

%*
0

An improvement on Andrei Ghimus's answer.

function time {
    $Command = $MyInvocation.Line -Replace ("^$($MyInvocation.MyCommand) ", "")
    Measure-Command { Invoke-Expression $Command | Out-Default }
}

The use of MyInvocation allows obtaining the actual arguments which is important when the command contains double quotes.

I found the 2>&1 just hid stderr which isn't what I wanted.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.