Warp is a lot better at that than Windows is. I understand the scheduler and pager was basically written by a bunch of the old VM guys seconded in to clean it up for version 1.3 after the MS divorce.
I have both Warp and Windows partitions on this particular box; I can run so many more programs under OS/2 and retain responsiveness over Windows that it's not even amusing... more sad. Even Moz is pretty good on a P200, as long as you have at least 96MB RAM in the thing. It'll thrash like a pig if you need to switch to another big program (say WordPro for example) but after the switch is completed the programs perform very well.