64 bit memory usage

[Antoine Pitrou]

On Thu, 9 Dec 2010 17:18:58 +0000
Rob Randall <rob.randall2 at gmail.com> wrote:
> Basically the process runs at around 1% and it never seems to grow in size
> again.
> When running the C++ with python app the process slows when a new 'page' is
> required but then goes back to 'full' speed. It does this until basically
> all the virtual memory is used.

Intuitively, Benjamin Kaplan had the right answer: Python will
periodically walk the heap of objects to look for dead reference cycles
to collect; if your working set is larger than the available RAM, then
this will thrash the pagefile to death.

So try gc.disable() before doing your tests.

I would stress that, of course, you will still have performance problems
as soon as you start using all those areas you are allocating. And if
you don't use them, I guess there's no point allocating them either. So
I don't know what exactly you're trying to do (is this an actual
application? or just some random test you're doing?), but relying on
the pagefile to have more available memory than the system RAM is a
very bad idea IMO.

Regards

Antoine.