PostreSQL v9.2 uses a lot of memory in Windows XP

Hi,

I had installed postgreSQL v9.2 in Windows XP SP3.

My PC specs:
Processor: Pentium Dual Core 2.09 GHz
RAM: 2GB

The postgreSQL is run as windows service (manual).

The problem is the postgreSQL service uses a lot of memory and lags
the OS if running in long time (about 2 hours or more) so I had to
restart the postgreSQL service everytime it happened. I never do any
big querying process so far. I only ever run it for adempiere ERP
software and a small struts 2 project.

See this screenshot link from the Process Explorer:

http://i45.tinypic.com/vr4t3b.png

You can see that there are a lot of threads spawned. Is the threads
that caused the high memory usage?

Is there a way to decrease the memory usage?

Thanks & Regards,
WM