mmap caching

[Laszlo Nagy]

> It's around 400MB. As I said, I cannot reproduce the MemoryError
> locally since I have 1GB physical space but IIRC the user who reported
> it had less. Actually I am less concerned about whether a MemoryError
> is raised or not in this case and more about the fact that even if
> there's no exception, the program may suffer from severe thrashing due
> to constant swapping. That's an issue with the specific
> program/algorithm rather with Python or the OS.
>   
Well, if the same program runs when you have 1GB physical memory then 
probably the problem is not that you ran out of virtual address space. 
It would help to provide the related code from your program.

  Laszlo