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Optimising WMI calls–part 2

Posted by: | August 30, 2016 Comments Off on Optimising WMI calls–part 2 |

Last time we looked at using CIM sessions to make a set of WMI calls run quicker. This time we’ll reduce the number of calls.  I’m deliberately just reducing the number of calls to the Win32_Service class.  We’ll look at the disks another time


Our code becomes

Measure-Command -Expression {

$srvs = ‘W16TP5TGT01’, ‘W16TP5TGT02’

for ($i=1; $i -le 150; $i++){

foreach ($srv in $srvs) {
$cs = New-CimSession -ComputerName $srv
$bootupMemory = Get-CimInstance -Query "SELECT * FROM Win32_OperatingSystem" -CimSession $cs
$cpuLoad = Get-CimInstance -Query "SELECT * FROM Win32_Processor" -CimSession $cs

$tSessions = Get-CimInstance -Query "SELECT * FROM Win32_TerminalService" -CimSession $cs

$sfilt = "Name=’imaservice’ OR Name=’mfcom’ OR Name=’cpsvc’ OR Name=’msmq’"
$reqserv = Get-CimInstance -ClassName Win32_Service -Filter $sfilt -CimSession $cs
$ima = $reqserv | where Name -eq ‘imaservice’
$mfcom = $reqserv | where Name -eq ‘mfcom’
$ctxPrintMgr = $reqserv | where Name -eq ‘cpsvc’
$msmqstatus = $reqserv | where Name -eq ‘msmq’

$cDrive = Get-CimInstance -Query "SELECT * FROM Win32_Logicaldisk WHERE deviceid=’c:’" -CimSession $cs
$dDrive = Get-CimInstance -Query "SELECT * FROM Win32_Logicaldisk WHERE deviceid=’d:’" -CimSession $cs
Remove-CimSession -CimSession $cs


The change is to create a filter that pulls back JUST the services we want. Use that to create a collection of Win32_Service objects and then populate the variables with the required service data


Time drops dramatically

Days              : 0
Hours             : 0
Minutes           : 6
Seconds           : 50
Milliseconds      : 133
Ticks             : 4101339515
TotalDays         : 0.0047469207349537
TotalHours        : 0.113926097638889
TotalMinutes      : 6.83556585833333
TotalSeconds      : 410.1339515
TotalMilliseconds : 410133.9515


Total time goes from 539.42 seconds to 410.13 seconds.  That’s reduced the time by 23.96%


These are just simple coding changes remember- we’re not performing any clever parallel processing here

under: PowerShell and CIM, PowerShell and WMI

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