Tobias Oberstein wrote: > Anyway, one more related thing: the GC (also the planned new one) > does GC per VM instance .. nothing global .. so I can run concurrent > GC : concrruent in the sense multiple VMs collected in parallel (not > concurrent in the sense within 1 VM), right? Yes the (current and new) GC is isolated per VM. The current GC can share a common allocator (needs locking of course), the new one can't. Every isolated allocator needs its own range of aligned memory blocks. E.g. cutting every instances down to use only (say) 10KB, will reduce the resident set size. But you still need 128KB minimum of virtual memory for each instance. Thus the number of instances and their efficiency is constrained due to virtual address space and page table overhead, rather than physical memory. --Mike