Powershell can be painfully slow when dealing with larger arrays, reading files and listing large directories. Here are some workarounds.
Arrays
Slow:
$myarray = @()
foreach ($x in $y) {
$myarray += $x
}
Much faster is working with an arraylist:
$myarray = [System.Collections.ArrayList]@()
foreach ($x in $y) {
$null = $procarray.Add($x)
}
Reading files
Slow:
get-content $filename
Fast:
([System.IO.File]::ReadAllLines($filename))
Listing large directories
Slow:
$items = get-item "\\server\share\*.csv" | sort LastWriteTime
The fastest workaround i’ve been able to find is actually using a dos prompt. Use dir switches for sorting purposes.
Note: dir returns just text, while get-items returns objects with all sorts of properties. It depends on your use case whether this hack is actually usable or not.
$items = cmd /r dir "\\server\share\*.csv" /OD /B