Setting CPU Priority on NT/Citrix?

Broue Master asks: "I was recently faced with the task of finding a way to prevent some users from taking 100% cpu time in Citrix. I'm no MS certified anything (but I am a Citrix certified admin) and I couldn't find a built in way to do this. After someone on the NTSysAdmin List suggested trying to set the CPU priority to low from the command line, I investigated and found a small freeware that did the trick: PrioSet. I don't have a big user base: 3 power users (who are my problem with their Access and Excel use) and 10 regular users (and the people most affected by the problem). I'd like to know if any of you have previously tried this software, or if you've run into the particular problem when one user is getting 99% of the CPU for a long time while all other users only share the spare 1%. Did the software solve the problem or did you solve the situation by other means?"

Comments

command line

[sql*kitten]

After someone on the NTSysAdmin List suggested trying to set the CPU priority to low from the command line, I investigated and found a small freeware that did the trick: PrioSet.

Type start /? into the prompt - it can start processes at different priorities. So you can replace direct shortcuts to your applications with .bat files that in fact start the application at a different priority.

Easy

[duffbeer703]

Change the shortcut that users launch Access & Excel with to point a CMD, shell or Perl script that launches Access or Excel, then sets drops the priority. It's pretty easy to use Perl to launch and control office applications.

Another route may be to move the access database to an RDBMS, which may use less CPU horsepower than using Access as a client/server.

Might not apply, but

[Asprin]

If the problem is 16 bit DOS apps, Tame can help.

Also, when you installed Office, did you run the appropriate app-tuning script afterward? (Search in x:\wtsrv for *.cmd and you'll find a whole bunch of them.) These scripts can make a big difference with certain versions of Windows.

You might also try the MetaFrame Installation and Tuning Tips. You might find a more recent version if you dig around.

why are you asking this here?

[kevin lyda]

ask microsoft or citrix. go buy their books or their cdrom reference libraries.

you paid for licenses and support, now go get your money's worth. why are you asking a bunch of (mainly) free software people who probably don't know the best answer?

and if you think we do, why don't you use the software we use?

A similar problem

[Kj0n]

I once heard of a similar problem with a NT server running Terminal Server and several users accessing it from a UNIX machine. The CPU usage of Excel would suddenly go to 100% and stay there.

Apparently, users used Shift + arrow key to switch to another virtual desktop. Unfortunately Excel went into a busy loop after the Shift key was pressed (it was busy waiting for the next key) and stayed there until the user switched back to the Terminal Server window. This resulted in Excel taking the entire CPU.

Re:Throttle the processes programmatically

[borgboy]

Actually, if he's running Win2k server, he can use the Job Object API
This API allows you to set per-process limits on cpu, memory, user mode execution time, min/max working set, processor affinity, thread priority, UI restrictions, and security restrictions.
I believe that Win2k Datacenter Server comes with a Job Object MMC for creating Job Objects / adding processes to a Job Object.

Re:ulimit? jeez

[larien]

Ulimit isn't the same thing; ulimit limits on total CPU time, not % CPU at any given time.

Thus, if they run an app for some time (e.g. over a few days) they might run up 30 minutes total CPU time with no real problems. On the other hand, someone could start an app, peg it at 99% for 10 minutes and completely hammer the server.

Operating systems like Solaris have add-ons to achieve system limits like CPU allocations to individual users/groups, but that is NOT ulimit.