Comments on: Split-Job: make your PC work harder

By: Tim

Tim — Tue, 16 Nov 2010 15:54:37 +0000

I really like this possibility, but I am so new at PS that while I understand the concept, I am still in the process of looking up commands and seeing what I can do.

I have PS script that gets eventlogs from about 150 computers. It works, but is slow. I want to incorporate the split-job function into my script but like I said, it is all new to me.

How do I manipulate your script to pull in what I have already written?

Thanks for helping out a newbie!

By: Practical PowerShell » Split-Job 0.92

Practical PowerShell » Split-Job 0.92 — Fri, 20 Jun 2008 01:48:32 +0000

[...] is an update to the Split-Job function. Based in part on some of the comments on the previous version, I made the following [...]

By: admin

admin — Tue, 10 Jun 2008 20:56:02 +0000

Thanks for your comments Stephen. Originally I did use a ScriptBlock as the input command but I was trying to make the syntax a bit cleaner when you need a foreach. In version 0.8, the usage looked like this:

"Server1","Server2","Server3" | Split-Job { c:\test.ps1 -Force }
"Server1","Server2","Server3" | Split-Job { % {gwmi Win32_ComputerSystem -ComputerName $_} }

Please note that you cannot use "foreach" instead of "%" here. Let me know what you think – I will consider rolling this back for the next version.

Regarding your earlier question about variables and profiles: I believe that is a common limitation when dealing with runspaces. I have not run into any situations where this was a problem (as long as you don't use custom aliases in your script, which you shouldn't anyway). I am planning to go into more detail about these pitfalls and how to avoid them in an upcoming post.

Cheers,
Arnoud

By: Stephen Mills

Stephen Mills — Tue, 10 Jun 2008 18:50:49 +0000

How do you use Cmdlets with parameters? I've played with it for a while and realized that I can't easily use parameters on Cmdlets as a command for Split-Job. I created a simple test.ps1 to demonstrate the issue. The first example thinks that -Force is a parameter of Split-Job. The second one doesn't process correctly for the pipeline, it doesn't see it as a pipeline. The third one works, but is non-intuitive. Example 4 also works, but could cause major headaches if you are already using both types of quotes.

One possiblity that might work, would be to require a script block and then at least the second example would work. You could also add a $Foreach switch parameter to do the same thing it currently does automatically if it is a scriptblock. I think I would just use script blocks and not use the $Foreach switch parameter. That way it is consistent with what it is replacing.

File: C:\Test.ps1
#### Begin File ###
param ([switch]$Force)
process
{ if ($Force) {$_} }
#### End File ####

C:\> "Server1","Server2","Server3" | Split-Job c:\test.ps1 -Force
C:\> "Server1","Server2","Server3" | Split-Job { c:\test.ps1 -Force }
C:\> "Server1","Server2","Server3" | Split-Job { $_ | c:\test.ps1 -Force }
Server1
Server2
Server3
C:\> "Server1","Server2","Server3" | Split-Job 'c:\test.ps1 -Force'
Server1
Server2
Server3

Thanks,

Stephen

By: karl prosser

karl prosser — Sat, 07 Jun 2008 04:42:25 +0000

this looks like a keeper. will have to look into it more.

By: Stephen Mills

Stephen Mills — Fri, 06 Jun 2008 20:47:08 +0000

Looks like a good script. I'll probably use it some. Is there anyway to duplicate your current environment in the runspaces? Sometimes you have variables you'd like to reference and profiles you need to have loaded.

You might want to check the $Pipelines.Count again before the start-sleep. That way it wouldn't pause once more after it is done.

Thanks