In yesterday's "Fast VM" thread I asked about memory consumption of PyPy vs. CPython, because most of the benchmarks focus on speed and there usually are no memory consumption figures (iirc, they were huge for Unladden Swallow [~800megs on one of their benchmarks, probably the django benchmark]). While I agree with fijal that there are no benchmarks stressing the memory sub-system, I think it would also be interesting for many potential early adopters to know about expected requirements.