Webmin and Squid Cache

I have had trouble with the Squid cache gobbling up my hard disc over
time, using Webmin I see that the cache limit is set '5500' and that
Webmin adds Mb on the screen. Before I reduce this to a size that is
less than my HDD I wanted to check that this is actually telling me
that I have a limit set to over 5Gb.
if I change this in Webmin, will I also have to clear aand rebuild
the cache?

Thanks for the help this newslist has been most helpful

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Simon Bryan                    simon@olmc.nsw.edu.au
Information Technology Manager sbryan@mpx.com.au
OLMC Parramatta