We have a batch file running every morning which does quite cpu-intensive calculations for about 2 hours.

Could someone point me to how I can do the following??

1. run the batch file's one and only command -- I assume that the existing batch file command will transfer over:

C:\U\8\US\Bin\TransProc.exe -Um -P88 -S4 -L9 -CMLS -MBM

2. then immediately set the transproc.exe process to LOW

My guess is that the the script would be:

C:\U\8\US\Bin\TransProc.exe -Um -P88 -S4 -L9 -CMLS -MBM
(transproc.exe).priorityclass="Low" or "BelowNormal", whichever works best

Or is there is another way where I could/should get the process ID of the TransProc.exe process, then set the process ID to Low??

After the batch file is done the TransProc.exe file is done, no worries thereafter...

Thank you, Tom

You can do something like this:

$startInfo = New-Object System.Diagnostics.ProcessStartInfo
$startInfo.Arguments = "-Um -P88 -S4 -L9 -CMLS -MBM"
$startInfo.FileName = "C:\U\8\US\Bin\TransProc.exe"

$process = New-Object System.Diagnostics.Process
$process.PriorityClass = [System.Diagnostics.ProcessPriorityClass]::BelowNormal
$process.StartInfo = $startInfo

$process.Start().WaitForExit()

wow...elegant...you are a PS ninja...!!

I am not a programmer and my two-liner air code would have been my way of doing this...

I can also see that this is quite re-usable code, in a true ninja style...!!

Thank you..!!

P.S. Do you have any suggestions how I can guarantee that PS really does wait over 2 hours for this process to finish?? and doesn't prematurely exit?? It's a super important calculation.

WaitForExit() waits indefinately for the process to exit, so the script will only stop once it has received some sort of return value from it no matter how long that is.

OIC -- I looked it up to see what it does and also encountered complaints about it not working properly.

Is there any particular reason why you need to keep the runspace ("script") alive once you've started the process?

Not longer than it takes to run the script, just not have the script stop calculating PRE-maturely.
All the calculations must run every morning, start to finish.

If the process stops prematurely, then that is the process' problem. All PowerShell is doing is starting it then off the process goes on its merry way. You do have the option inspecting the exit code however (which takes two possible forms), which can help with debugging:

$process.Start().WaitForExit()
$process.ExitCode

OR

$process.Start()
Wait-Process -InputObject $process
$process.ExitCode

OIC -- I can have a success message etc. like so??

If $process.ExitCode = 0 then
$body = Success;
else
$body = "fubar" + $process.ExitCode;

send email

Precisely.