Python 2.5 consumes more memory than 2.4.4

Since python 2.5 contains a new object allocator that is able to return memory to the operating system, I was surprised to find that python 2.5.1 consumes more memory at start-up than 2.4.4 does (at least on Windows). I have been assuming that 2.5.1 could only use the same or less memory than python 2.4.4. However, simply starting each interactive interpreter on my Windows XP machine, the Task Manager reports:

Version	"Mem Usage"	"VM Size"
Python 2.4.4	3440k	1788k
Python 2.5.1	5828k	3868k

The specific builds tested where:

• Python 2.4.4 (#71, Oct 18 2006, 08:34:43) [MSC v.1310 32 bit (Intel)] on win32
• Python 2.5.1 (r251:54863, Apr 18 2007, 08:51:08) [MSC v.1310 32 bit (Intel)] on win32

Which were installed using the Windows Installers on the python.org web site as of today.

Of course, depending on your application, I would expect python 2.5.1 to still use less memory overall. But what surprised me was how much of a handicap python 2.5.1 has after just loading the interpreter: it starts out consuming over 2 megabytes more memory.