How to use powershell background jobs to delete a SPListItem

Question

I want to delete items from a document library using powershell 2.0, but not all of them, only ones that pass some of my if statements (and no I can't use CAML for all my conditions). So I have to loop through the items and then delete it. Except it takes so long to delete all the items. So I want to use background jobs. I have this code:

$spListItem = .....; # I get the item here
$task = {
    PARAM($spListItem);
    $spListItem.Delete();
}
$job1 = Start-Job -ScriptBlock $task -ArgumentList $spListItem;

but this code is not working. Does anyone know what is wrong?

ERROR:

Method invocation failed because [Deserialized.Microsoft.SharePoint.SPListItem] doesn't contain a method named 'Delete'.
    + CategoryInfo          : InvalidOperation: (Delete:String) [], RuntimeException
    + FullyQualifiedErrorId : MethodNotFound

Answer 1

Here I've found An SPListItem is not serializable

I've tried to create a workaround - it could work but it loses an advantage of "parallel" jobs because start time and memory costs are greater than "serial" running

$cmd = {
  param($url, $listName, $id) 
  Add-PSSnapin Microsoft.SharePoint.PowerShell
  $web = get-spweb -identity "$url"
  $list = $web.Lists["$listName"]   
  $list.GetItemById($id).Delete(); 
  write-host $id}

foreach  ($item in $items)
{           
  start-job -scriptblock $cmd -argumentList $url, $listName, $item.id       
}

If you'll find better solution please share it...