Vista - Performance of PowerShell (v1.0) vs WSH (v5.6)

I have problem with Performance of my script in PowerShell.
It is very slow.

For testing of performance I created 2 simple scripts (see below). First in
PowerShell and second in WSH.
Both do the same (Only 2 empty nested cycles).

* PowerShell version running for 367 seconds.
* WSH version running for 23 seconds.
Is it possible that PowerShell is about 16 times slower than WSH?
Or mistake is somewhere else?

* PowerShell-script is:
....
/------------------------------------8<----------------------------------\
$I = [int]
$S = [string]
$X = [int]
[int]$Limit = 10000
[datetime]$TimeStop = Get-Date
[datetime]$TimeStart = Get-Date

$S = "*** Limit is: {0:N0}" -f $Limit
Write-Host $S
$S = "*** Start at: {0:dd}:{0:MM}:{0:yyyy} {0:HH}:{0:mm}:{0:ss}, wait please
.... " -f $TimeStart
Write-Host $S

for ($I = 1; $I -le $Limit; $I++) {
$X = 0
While ($X -lt $Limit) {
$X++
}
}

$TimeStop = Get-Date
$TimeDuration = $TimeStop - $TimeStart

$S = "*** Stop at : {0:dd}:{0:MM}:{0:yyyy} {0:HH}:{0:mm}:{0:ss}." -f
$TimeStop
Write-Host $S
Write-Host "*** Duration: $TimeDuration"

\------------------------------------8<----------------------------------/
....

* and WSH-script is:
....
/------------------------------------8<----------------------------------\
option explicit
Dim I, Limit, S, TimeDuration, TimeStart, TimeStop, X

Limit = 10000
TimeStart = Now
TimeStop = Now

Wscript.Echo "*** Limit is: " & CStr(Limit)

Wscript.Echo "*** Start at: " & CStr(TimeStart) & ", wait please ..."

For I = 1 To Limit
X = 0
While X < Limit
X = X + 1
Wend
Next

TimeStop = Now
TimeDuration = TimeStop - TimeStart

Wscript.Echo "*** Stop at : " & CStr(TimeStop)
S = Right("0" & CStr(Day(TimeDuration)),2)
S = S & "." & Right("0" & CStr(Month(TimeDuration)),2)
S = S & "." & Right("0" & CStr(Year(TimeDuration)),2)
S = S & " " & Right("0" & CStr(Hour(TimeDuration)),2)
S = S & ":" & Right("0" & CStr(Minute(TimeDuration)),2)
S = S & ":" & Right("0" & CStr(Second(TimeDuration)),2) & " ("
Wscript.Echo "*** Duration: " & S & CStr(TimeDuration) & ")"
\------------------------------------8<----------------------------------/
....

P.S.
I ran this scripts repeatedly on the same computer:
* notebook lenovo ThinkPad T400,
* CPU=Intel Core 2 Duo, 2.40 GHz,
* RAM=1.94GB
* OS = Microsoft Windows XP + SP2 [Version 5.1.2600]

In this case, you should compare your vbs to following code (sorry,
just quick & dirty rewrite):

$S = [string]
[int]$Limit = 10000
[datetime]$TimeStart = Get-Date


$S = "*** Limit is: {0:N0}" -f $Limit
Write-Host $S
$S = "*** Start at: {0:dd}:{0:MM}:{0:yyyy} {0:HH}:{0:mm}:{0:ss}, wait
please
.... " -f $TimeStart
Write-Host $S

While ($I -le $limit) {
$I++
$X = 0
While ($X -lt $Limit) {
$X++
}
}


$TimeDuration = $(Get-Date) - $TimeStart

$S = "*** Stop at : {0:dd}:{0:MM}:{0:yyyy} {0:HH}:{0:mm}:{0:ss}." -f
$TimeStop
Write-Host $S
Write-Host "*** Duration: $TimeDuration"


Notice that I use While also in Posh example.

Interesting thing is that when I tried it, Posh was much faster when
limit was lower (up to 1000), however got slower and slower than
vbscript afterwards.

Martin

BTW you should check cmdlet Measure-Command

Good idea!
It is more efficient.
Thank you very much.
;-)

Now my script looks like this:
/------------------------------------8<----------------------------------\
$I = [int]
$S = [string]
$X = [int]
[int]$Limit = 1000
[datetime]$TimeStart = Get-Date

$S = "*** Limit is: {0:N0}" -f $Limit
Write-Host $S
$S = "*** Start at: {0:dd}:{0:MM}:{0:yyyy} {0:HH}:{0:mm}:{0:ss}, wait please
.... " -f $TimeStart
Write-Host $S

Measure-command {
for ($I = 1; $I -le $Limit; $I++) {
$X = 0
While ($X -lt $Limit) {
$X++
}
}
}
\------------------------------------8<----------------------------------/


"Martin Zugec" <martin.zugec@newsgroup> wrote in message
news:24bdda70-cbb5-4589-8409-9c7ef8a9cf1b@newsgroup

Another way (the one I use quite often for benchmarking, if I want to
test different approaches):

1.) Create few different scenarios - in your case, create Test.ps1 and
Test.vbs

2.) From Powershell session, run each one of this script using Measure-
Command

Martin

+ 1 more thing... You should change both scripts to support -Limit
argument. Then you can automate test and see what will be difference
in execution time.

As I said, I spend just few minutes on this, however I could see that
Posh is much faster with lower limit and vbscript is much faster once
limit get higher. It would be nice to see some graph or something

If you (for whatever reason) don't want to spend too much time with
it, let me know and I will write blog post about it

Martin