Skip to main content

Using Calculated Properties to get Command Execution Time

We are finishing up day 1 here in my PowerShell class in Hunt Valley, MD.  Just finished up calculated properties and had a request to expand the demonstration that I used a bit.  We were using the Get-History cmdlet to explore calculated properties.  Here is the code and output that we had:

Get-History |

    Select-Object -Property CommandLine,

    @{N="ExecutionTime";

        E={$_.EndExecutionTime - $_.StartExecutionTime}} |

    Sort-Object -Property ExecutionTime -Descending |

    Select-Object -First 5

CommandLine                              ExecutionTime                          

-----------                              -------------                          

Show-Command                             00:01:48.0548277                       

Update-Help                              00:00:27.2509743                       

Get-Process | Select-Object -Property... 00:00:07.7695634                       

Get-Service -Name BITS | Stop-Service... 00:00:05.8634245                       

get-eventlog                             00:00:05.4523953            

 

The question came up if there is an easier way to display the ExecutionTime property.  Our first step was to pipe this information to Get-Member to see the object type.

Get-History |

    Select-Object -Property CommandLine,

    @{N="ExecutionTime";

        E={$_.EndExecutionTime - $_.StartExecutionTime}} |

    Sort-Object -Property ExecutionTime -Descending |

    Select-Object -First 5 |

    Get-Member

    TypeName: Selected.System.Management.Automation.PSCustomObject

 

Name          MemberType   Definition                                   

----          ----------   ----------                                   

Equals        Method       bool Equals(System.Object obj)               

GetHashCode   Method       int GetHashCode()                            

GetType       Method       type GetType()                               

ToString      Method       string ToString()                            

CommandLine   NoteProperty System.String CommandLine=Show-Command       

ExecutionTime NoteProperty System.TimeSpan ExecutionTime=00:01:48.0548277

 

I highlighted in red the object type.  Our next step was to extract the value of this property and send it to Get-Member to see what properties we had to work in the object type System.TimeSpan. As an alternate to this next step, just go to MSDN and look up the .NET object System.TimeSpan.  

Get-History |

    Select-Object -Property CommandLine,

    @{N="ExecutionTime";

        E={$_.EndExecutionTime - $_.StartExecutionTime}} |

    Sort-Object -Property ExecutionTime -Descending |

    Select-Object -ExpandProperty ExecutionTime |

    Get-Member

    TypeName: System.TimeSpan

 

Name              MemberType Definition                                         

----              ---------- ----------                                         

Add               Method     timespan Add(timespan ts)                          

CompareTo         Method     int CompareTo(System.Object value), int CompareTo...

Duration          Method     timespan Duration()                                

Equals            Method     bool Equals(System.Object value), bool Equals(tim...

GetHashCode       Method     int GetHashCode()                                  

GetType           Method     type GetType()                                     

Negate            Method     timespan Negate()                                  

Subtract          Method     timespan Subtract(timespan ts)                     

ToString          Method     string ToString(), string ToString(string format)...

Days              Property   int Days {get;}                                    

Hours             Property   int Hours {get;}                                   

Milliseconds      Property   int Milliseconds {get;}                            

Minutes           Property   int Minutes {get;}                                 

Seconds           Property   int Seconds {get;}                                 

Ticks             Property   long Ticks {get;}                                  

TotalDays         Property   double TotalDays {get;}                            

TotalHours        Property   double TotalHours {get;}                           

TotalMilliseconds Property   double TotalMilliseconds {get;}                    

TotalMinutes      Property   double TotalMinutes {get;}                         

TotalSeconds      Property   double TotalSeconds {get;}    

 

We decided that the property TotalSeconds would be the best one to use in our scenario. In the Expression of the calculated property in line 4, we encapsulate our original expression inside of parenthesis. This allowed us to dot out the property of TotalSeconds from the object with minimal adjustment to our code.

Get-History |

    Select-Object -Property CommandLine,

    @{N="ExecutionTime";

        E={($_.EndExecutionTime - $_.StartExecutionTime).TotalSeconds}} |

    Sort-Object -Property ExecutionTime -Descending |

    Select-Object -First 5

CommandLine                                                         ExecutionTime

-----------                                                         -------------

Show-Command                                                          108.0548277

Update-Help                                                            27.2509743

Get-Process | Select-Object -Property...                                7.7695634

Get-Service -Name BITS | Stop-Service...                                5.8634245

get-eventlog                                                            5.4523953

 

And there you have it.  If you have several ideas on how to accomplish a task, you can use this method to determine which one is most efficient.  You may need to utilized TotalMilliseconds in a test environment for greater precision.  If your task includes reaching out to clients on the network, the network traffic and client availability will have an effect on the times reported.  It is best to test on a local system to determine the most efficient command.

Comments

Popular posts from this blog

Determine which Domain Controller a client is connected to with PowerShell

When a Windows client comes online, it must find a domain controller to bind to.  Either through a static configuration or DHCP, the client will request a list of all Domain Controllers in the domain from a DNS server.  Once the list is received, the client will randomly go through the list to find a DC that will respond.  Once the client has authenticated itself with the DC, the DC will transmit the site information to the client.  The site information will contain the site name, the subnet(s) associated with that site, and any domain controllers in that site.  The client will then take a look at it’s own IP address to determine which site it is in.  From the list of DCs in the same site, it will attempt to bind to one of those DCs to receive it’s Group Policies.You can use PowerShell and WMI to locate the domain controller that a client is connected to.Get-WMIObject Win32_NTDomainLook for the DomainControllerName property.

Test to see what that data type of a value is in PowerShell

PowerShell has a comparison operator called –is.  The –is operator simply response True or False when you use it to verify the data type of a value.  The valid data types in PowerShell are:
[string]    Fixed-length string of Unicode characters
[char]      A Unicode 16-bit character
[byte]      An 8-bit unsigned character
[int]       32-bit signed integer
[long]      64-bit signed integer
[bool]      Boolean True/False value
[decimal]   A 128-bit decimal value
[single]    Single-precision 32-bit floating point number
[double]    Double-precision 64-bit floating point number
[DateTime]  Date and Time
[xml]       Xml object
[array]     An array of values
[hashtable] Hashtable object

Below is a script that will use –is to test some values.
$String="Hello"$Boolean=$True$Int=15Write-Host"Test for string"$String-is [String] $Boolean-is [String] $Int-is [String] Write-Host" "Write-Host"Test for Boolean"…

Where did a User’s Account Get Locked Out?

Updated: May 15, 2015
When this article was originally published, two extra carriage returns were add causing the code to malfunction.  The code below is correct.  

My client for this week’s PowerShell class had a really interesting question. They needed to know where an account is being locked out at. OK, interesting. Apparently users hop around clients and forget to log off, leading to eventual lock out of their accounts. The accounts can be unlocked, but are then relocked after Active Directory replication.
This problem is solved in two parts. The first one is to modify the event auditing on the network. The second part is resolved with PowerShell.
The first part involves creating a group policy that will encompass your Domain Controllers. In this GPO, make these changes.
Expand Computer Configuration \ Policies \ Windows Settings \ Security Settings \ Advanced Audit Policy Configuration \ Audit Policies \ Account ManagementDouble click User Account ManagementCheck Configure the f…