in reply to Set thread quantum for process under Windows

Type start /? on your command line for how to start a command with a low or background priory.

Hit ctrl-alt-del to bring up the task manager, right-clock the name on the processes tab and use "set Priority" ona running process.

See Win32::Process and use the appropriate constant from:

        HIGH_PRIORITY_CLASS
        IDLE_PRIORITY_CLASS
        NORMAL_PRIORITY_CLASS
        REALTIME_PRIORITY_CLASS
        THREAD_PRIORITY_ABOVE_NORMAL
        THREAD_PRIORITY_BELOW_NORMAL
        THREAD_PRIORITY_ERROR_RETURN
        THREAD_PRIORITY_HIGHEST
        THREAD_PRIORITY_IDLE
        THREAD_PRIORITY_LOWEST
        THREAD_PRIORITY_NORMAL
        THREAD_PRIORITY_TIME_CRITICAL
        ABOVE_NORMAL_PRIORITY_CLASS
        BELOW_NORMAL_PRIORITY_CLASS

[download]

if you are starting the process from within perl.

Personally, I find the first option the simplest even when starting a process from with a perl script:

system q[start /low notepad.exe];;

[download]

as it also allows me to set the affinity mask.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

The start of some sanity?

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Re^2: Set thread quantum for process under Windows
by chessgui (Scribe) on Jan 05, 2012 at 10:19 UTC
    Thanks a lot. These seem to be useful starting points. But my main goal is to do this on a constant basis (ie. not having to look my process up in the table manually every time rather do it automatically from the script) and having a look at the Win32::Process module it seems to me that if I open the process that way I won't have handles to the STDIN and STDOUT of the process, while if I open it through Open2 (as I do currently) there is not a Win32::Process object on which I can perform $ProcessObj->SetPriorityClass($class). There seems to be no method for creating a Win32::Process object from a pid.
[reply]
      There seems to be no method for creating a Win32::Process object from a pid.

      Actually there is:

      Win32::Process::Open( $obj, $pid, $iflags );

      [download]

      $pid is an existingprocess id as return by open2(), $obj is a variable you pass in which gets set to a Win32::Process object handle. You can the call ->SetPriority() on that. Eg.

      use Win32::Process;;

$pid = system 1, 'notepad';; ## The return from open2 should work just
+ as well.

Win32::Process::Open( $o, $pid, 0 );;

print $o;;
Win32::Process=SCALAR(0x4073208)

$o->SetPriorityClass( IDLE_PRIORITY_CLASS );;

      [download]
      With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
      Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
      "Science is about questioning the status quo. Questioning authority".
      In the absence of evidence, opinion is indistinguishable from prejudice.

      The start of some sanity?
[reply]
[d/l]
[select]
        How could I have missed this?
[reply]

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