Strange slowdown due to cache ?

Here's a couple of things I've noticed about the SL cache on my machine. I've been watching this for some time now and it concerns me ...

- Frame rate gets slower as cache gets larger.
During hours of play my frame rate will drop to as low as 6fps in my home area which I know is usually around 15 to 25 fps. If I log off and delete the cache frame rate goes back up to the usual speed, more than doubling my performance.

- Cache size on disk bears no relation to cache size option in Prefs.
The two simply are not connected. It doesnt matter what I set prefs cache size to the number and size of disk files will keep growing. Yesterday I deleted over a gig of cache.

Anyway point is: i thought the point of a cache was to improve performance ?
Surely these are major bugs ? Lindens care to comment ? Should I file a report or is this a "Known Issue" ?

Ive experienced the same problem.

It seems that when you exit a sim and tp back to it, most of the cache seems to be overwritten, cuz all textures becomes grey and starts loading up again.

Mostly tho it seems as you said, if you use it for a long period of time, SL starts dropping in performance alot, and when deleting the cache everything works good again.

From my point of view it seems that the cachesystem doesnt know its files and just rewrite cachepoints,.. like it doesnt have a correct register for its files.

/ Max