ZBrushCentral

Is Zbrush supposed to run out of Free Mem after awhile and just start lagging?

ZBrush Usage Questions
#1

I know the more you have on the scene, the more ram it will need. However Ive been working on this one model of mine, 4.mill polys sculpting and polypainting, I noticed if i have it on for a few hours ill start seeing stuttering with OTHER programs I may have running the background.

I always notice Active Memory at the top slowly creeping higher and higher, the next thing i know my Free Mem is down to like .08 which again, I know zbrush is using it.

The problem is it lags other programs in the background. When I scramble to try and shut whatever program off, it turns out to be a waiting game and home zbrush and everything else doesnt crash.

Im assuming this is because zbrush is using all my ram?
Max I have is 8gb. Thats about the time I would use compact now but do I need to keep doing that?

How much ram would I need to never bother with it?

#2

Have you tried getting rid of some earlier history? I find that helps.

#3

Ive limited undo history just to see. Eventually it starts hogging all the memory and ill end up having to shut it down because of it. Restarting it gets it to work.

Intel I5 4460 3.20ghz
8GB ram
windows 7 64bit

Should I even be having issues with a 5mil subtool (10mil total across all subtools)? Really now I thought zbrush was supposed to be great performance wise, I dont see how 5 mil polys will drive up ram usuage to the point where anything in the background will become unusable thus needing a hard shut down.

Is it polypaint? The 5 mil model im working on has 4 UV tiles (udim) so is that it? I usually like to polypaint in zbrush but should I skip polypaint all together now?

I would really appreciate some help. Compact memory lightens the load but then I need to remember to click it everytime my ram craps out.