So this one might be pretty simple you say, just use measure-command right? But what if I already ran the command and didn’t time it? What if it took really long time and running it again isn’t an option?

This is when built-in history helps! If you run

Get-History | Get-Member

You will see the following:

   TypeName: Microsoft.PowerShell.Commands.HistoryInfo

Name               MemberType Definition
----               ---------- ----------
Clone              Method     Microsoft.PowerShell.Commands.HistoryInfo Clone()
Equals             Method     bool Equals(System.Object obj)
GetHashCode        Method     int GetHashCode()
GetType            Method     type GetType()
ToString           Method     string ToString()
CommandLine        Property   System.String CommandLine {get;}
EndExecutionTime   Property   System.DateTime EndExecutionTime {get;}
ExecutionStatus    Property   System.Management.Automation.Runspaces.PipelineState ExecutionStatus {get;}
Id                 Property   System.Int64 Id {get;}
StartExecutionTime Property   System.DateTime StartExecutionTime {get;}

Notice the properties “StartExecutionTime” and “EndExecutionTime”. For every command kept in PowerShell history, it keeps track of when it started and when it ended. To see how long it took to run the command, you can just use built-in math functionality. Here is how:

$h = get-history
$h[-1].EndExecutionTime - $h[-1].StartExecutionTime

The output would look something like this:

Days              : 0
Hours             : 0
Minutes           : 0
Seconds           : 0
Milliseconds      : 46
Ticks             : 467997
TotalDays         : 5.41663194444444E-07
TotalHours        : 1.29999166666667E-05
TotalMinutes      : 0.000779995
TotalSeconds      : 0.0467997
TotalMilliseconds : 46.7997

This also applies to your scripts. If you ran script, reported time will be how long script took to execute. It does not keep track of individual commands contained within your script but you already knew that, didn’t you?

Originally posted at http://blogs.technet.com/bshukla