Broken? That's a bit harsh.
Immature? That's perhaps a better explanation.
This paper describes Priority Paging as implemented in Solaris 2.7 back in 1998, and that's essentially what Mac OS X is in need of today:
The problem is that when pages are needed, no differentiation is made between system file cache pages and application pages, and worse, the file cache can actually steal pages needed by applications.
Finally when Dynamic Pager starts up and needs to start swapping things out, it's fairly heavy weight in operation, and causes the UI not responding cursor (aka the spinning beach ball) to appear.
i submited a bug report to apple.
i finally got an answer, but unfortunatly it is
The issue is being tracked under under the original Bug ID# ........ which is also listed in the Related Problem section of your bug report.
I can see that other bug listed as bug id#, but i cannot open it, search it ....
does anybody know how to open other people's bug report ?
I feel you pain and as someone with an oldish (early 2008) Al iMac with only 4 GB of RAM I feel your pain. Try running purge from the terminal. I find I need to do this about once a day. It will free up most of your Incative RAM.
You may need Developer Tools installed, I forget