Glib memory handling

[Yarick Rastrigin <yarick relex ru>]

well, could someone clear some points for me ?
I'm writing an app, which in turns creates quite large GList' s. 
I'm monitoring memory usage with qps. App requests and gets 8 Mbytes of
memory for it's purposes, after processing lists are freed with all
their contents. Howewer, data size of my app isn't decreased when all
done. How I could really free unnecessary memory ? Or this isn't
gtk/glib feature, but libc-related one ?
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Version: 3.1
GED/J d->-- a-- C++++$ UL+++ P@ L+++$ E+(-) W>+ N++(+++) o? K? w-->---
O-- !M 
V- PS++(+++) PE- !Y PGP- t? 5? X R* tv b++ d? D++ G++ e- h--- r+++ y+++  
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With all the best, Yarick Rastrigin
yarick@relex.ru AKA 2:5025/17