WLM Resource Capping

[JASONR]

In our installation, a couple of service classes were assigned to a single resource group (limit set at SU's/sec). Both the service classes were defined with the importance of 2 and velocity goals of 50 and 20 respectively. The high velocity service class is not meeting it's goals when the resource group gets capped. The low velocity service class has more tasks than the high velocity service class.Does WLM ignore the velocity goals when the resource group is capped? Any insight into this topic will be greatly appreciated.

[Tim.Browning]

Sometimes your goals for WLM can't be achieved or are too aggressive, and in those situations, a more modest goal has a better overall effect. You can have too many high level goals for too many tasks. Make a (10% - 80% - 10%) distribution with 'most favored' and 'least favored' tasks in the upper/lower 10%.

Also, with WLM, you can have too many service classes and policies for adjustments and measurements to be made during it's brief intervals of activation. It doesn't have time to complete before its time is up and so it seems to be ignoring your specifications.

Keep it simple and less aggressive. When that is working, then begin to tweak it a bit. When the last tweak has no effect...stop.

This probably doesn't answer your questions exactly, but it has worked for me in the past and the results have been useful. Large and elaborately detailed WLM specifications don't seem effective. I rarely change WLM specs and I don't think you want to tune systems with it on a frequent basis.

Best regards,

Tim Browning
Kimberly Clark
ITS Consultant - Capacity Planning & Performance
tim.browning@kcc.com