tkinter: not freeing memory like I'd expect

[Benjamin Rutt]

I have a bunch (e.g. 40) of tkinter Text objects in a gui on a linux
machine, tracking monitoring info per host. They accumulate up to
500MB of text data (according to /bin/top) over time reading from
sockets. I want to release this memory first by clearing all the text
contents, but keeping the Text objects in the GUI, via a callback
like:

def erase_all_text( ):
for h in known_hosts_tex ts.keys():
t = known_hosts_tex ts[h]
t.config(state= NORMAL)
t.delete('1.0', END)
t.config(state= DISABLED)

But after calling the function, although the texts are cleared, no
memory is released according to /bin/top (the process is still 500MB
large). Next, I try to remove all objects from the GUI, in the hope
that will free the memory:

def clear_all():
global known_hosts
global known_hosts_fra mes
global known_hosts_tex ts

known_hosts = {}
known_hosts_fra mes = {}
known_hosts_tex ts = {}

for w in frametop.childr en.values():
w.destroy()

Got those last 2 lines from a Fredrik Lundh post I think. But again,
the process is still 500MB large.

I should point out that the erase_all_text( ) and clear_all() do what
they're told for the GUI, appearance-wise, it's just that I'd expect
the memory footprint to be reduced when they are called. The lack of
a reduction eats up my memory space and causes the out-of-memory linux
killer to fire up eventually. Am I doing anything wrong in either of
my approaches? Or should I not expect memory to be released?
--
Benjamin Rutt