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Measure-Command

  • Reference
Module:
Microsoft.PowerShell.Utility

Measures the time it takes to run script blocks and cmdlets.

Syntax

Measure-Command
       [-InputObject <PSObject>]
       [-Expression] <ScriptBlock>
       [<CommonParameters>]

Description

The Measure-Command cmdlet runs a script block or cmdlet internally, times the execution of the operation, and returns the execution time.

Note

Script blocks run by Measure-Command run in the current scope, not a child scope.

Examples

Example 1: Measure a command

This example measures the time it takes to run a Get-EventLog command that gets the events in the Windows PowerShell event log.

Measure-Command { Get-EventLog "windows powershell" }

Example 2: Compare two outputs from Measure-Command

The first command measures the time it takes to process a recursive Get-ChildItem command that uses the Path parameter to get only .txt files in the C:\Windows directory and its subdirectories.

The second command measures the time it takes to process a recursive Get-ChildItem command that uses the provider-specific Filter parameter.

These commands show the value of using a provider-specific filter in PowerShell commands.

Measure-Command { Get-ChildItem -Path C:\Windows\*.txt -Recurse }

Days              : 0
Hours             : 0
Minutes           : 0
Seconds           : 8
Milliseconds      : 618
Ticks             : 86182763
TotalDays         : 9.9748568287037E-05
TotalHours        : 0.00239396563888889
TotalMinutes      : 0.143637938333333
TotalSeconds      : 8.6182763
TotalMilliseconds : 8618.2763

Measure-Command {Get-ChildItem C:\Windows -Filter "*.txt" -Recurse}

Days              : 0
Hours             : 0
Minutes           : 0
Seconds           : 1
Milliseconds      : 140
Ticks             : 11409189
TotalDays         : 1.32050798611111E-05
TotalHours        : 0.000316921916666667
TotalMinutes      : 0.019015315
TotalSeconds      : 1.1409189
TotalMilliseconds : 1140.9189

Example 3: Piping input to Measure-Command

Objects that are piped to Measure-Command are available to the script block that is passed to the Expression parameter. The script block is executed once for each object on the pipeline.

# Perform a simple operation to demonstrate the InputObject parameter
# Note that no output is displayed.
10, 20, 50 | Measure-Command -Expression { for ($i=0; $i -lt $_; $i++) {$i} }

Days              : 0
Hours             : 0
Minutes           : 0
Seconds           : 0
Milliseconds      : 12
Ticks             : 122672
TotalDays         : 1.41981481481481E-07
TotalHours        : 3.40755555555556E-06
TotalMinutes      : 0.000204453333333333
TotalSeconds      : 0.0122672
TotalMilliseconds : 12.2672

Example 4: Displaying output of measured command

To display output of expression in Measure-Command you can use a pipe to Out-Default.

# Perform the same operation as above adding Out-Default to every execution.
# This will show that the ScriptBlock is in fact executing for every item.
10, 20, 50 | Measure-Command -Expression {for ($i=0; $i -lt $_; $i++) {$i}; "$($_)" | Out-Default }

10
20
50


Days              : 0
Hours             : 0
Minutes           : 0
Seconds           : 0
Milliseconds      : 11
Ticks             : 113745
TotalDays         : 1.31649305555556E-07
TotalHours        : 3.15958333333333E-06
TotalMinutes      : 0.000189575
TotalSeconds      : 0.0113745
TotalMilliseconds : 11.3745

Example 5: Measuring execution in a child scope

Measure-Command runs the script block in the current scope, so the script block can modify values in the current scope. To avoid changes to the current scope, you must wrap the script block in braces ({}) and use the invocation operator (&) to execute the block in a child scope.

$foo = 'Value 1'
$null = Measure-Command { $foo = 'Value 2' }
$foo
$null = Measure-Command { & { $foo = 'Value 3' } }
$foo

Value 2
Value 2

For more information about the invocation operator, see about_Operators.

Parameters

-Expression

Specifies the expression that is being timed. Enclose the expression in braces ({}).

Type:ScriptBlock
Position:0
Default value:None
Required:True
Accept pipeline input:False
Accept wildcard characters:False

-InputObject

Objects bound to the InputObject parameter are optional input for the script block passed to the Expression parameter. Inside the script block, $_ can be used to reference the current object in the pipeline.

Type:PSObject
Position:Named
Default value:None
Required:False
Accept pipeline input:True
Accept wildcard characters:False

Inputs

PSObject

You can pipe an object to this cmdlet.

Outputs

TimeSpan

This cmdlet returns a time span object representing the result.