From Planimate Knowledge Base
Q:My model appears to have slowed down - the bar graph progresses a lot slower.
A:You either have a lot of activity over this period of time, or you may be running low on memory, and swapping a lot to disk, or you may have set up some behaviour where an item cycles around and around a lot at short intervals.
Unchecked table logging and holding excessive items (eg in queues) that are not actually required can cause this.
idkbase note 285
Planimate Knowledge Base