Bug or not

I update rails from 2.0.2 to 2.2.3, and I start server by ruby
script/server or mongrel_rails. But when I use my system, for test or
view, the system often exit auto and report a failed to allocate memory
I try to change the enviroment, then I found something. I have installed
ramdisk on my computer, if I remove it, the rails seemed normal, but if
I reinstall the ramdisk, it reoport error again and exit. The status is
not always but often if I install ramdisk.
It's bug or not?