Using Terrain Engine, Unity becomes slow, drags system down

Has anybody else experienced this?

Just for fun I experimented a bit with Unity's Terrain Engine. Not my main project, just for fun. Bought the "BIG Environment Pack" on the Asset Store and off we go. Terrain is only 100x100. Setup tree and flower models from the Pack. Use the terrain tool to place trees, 2d grass, 3d detail objects. All fine and good. The functionality is there. But ...

First of all, Unity after a while becomes dog slow. I don't see this in my main project, only in this project using the Terrain engine. Opening a fresh Unity with this project RAM usage is at approx. 350 MB, according to Mac OS X's Activity Monitor. Play around with the tools for a while, it goes to 500 MB any beyond, the Editor UI becoming slower and slower. Go in and out of Play mode a few times and you are at 800+ MB, the Editor becomes unusable. I see sometimes the RAM usage going down a bit, so I guess sometimes the Garbage Collector has way too much to do.

In the console I see a lot of this:

Code (csharp):

1. Dec 15 21:58:37 Mac-Pro.local WindowServer[126]: disable_update_timeout: UI updates were forcibly disabled by application "Unity" for over 1.00 seconds. Server has re-enabled them.
2. Dec 15 21:58:39 Mac-Pro.local WindowServer[126]: common_reenable_update: UI updates were finally reenabled by application "Unity" after 2.48 seconds (server forcibly re-enabled them after 1.00 seconds)

Try to edit the attributes of your terrain engine objects. You enter values in the dialog and the whole thing just freezes for a few seconds, then the updates become visible in the Preview. To unfreeze things again you want to re-start Unity and maybe the computer. Which bring use to ....

Secondly, Unity doesn't properly quit anymore. The Dock icon remaines visible, with the "open application" marker. It disappears from Activity Monitor though. It does not disappear from the force-quit dialog in Mac OS X. It does not have the red "does not respond" label to it (which crashing/hanging apps in OS X usually have). Selecting Unity for force quit does nothing, the dialog doesn't change.

Trying to shut down or restart the machine will quit all other apps but Unity, then it hangs. You can't open other apps during that time, since the on-going shutdown process immediately kills them. Double-clicking the Unity icon does nothing (since it is already open). Since shutting down the computer does nothing, you can only reset the machine.

I own the machine I am running Unity on for about nine months now and this is the first time ever I had to do this. The error I describe is reproducable, it has happened three times now, after varying lenghts of playing around with the Terrain Engine.

My impression is that the Unity Terrain Engine has it's problems. Anybody else seing this?

Unity3D Free 4.3.0f4
Mac OS X.9.0
CustoMac (Intel i5, Z77 motherboard, GeForce GTX 650 Ti)

 

Uhm, I just experienced the same error (Unity not closing fully down upon quit, unable to re-open it), but working on my main Unity project, which does not use the Terrain engine.

In system.log, it says

However, this is the first time this happened on my main project.