memory overflow?

[patrickk]

sorry if this is a stupid question, but I don´t have much experience  
using memcache.

we launched a site 2 days ago where we use memcache with the django- 
framework.
we have about 10 pages in the cache.
now, the cache status is at:
# memory usage: 238.7 MB
# keys in cache: 5880 of 46353
# cache hits: 263048 of 288603: 91%

i´m a bit worried about the memory usage and the huge amount of keys  
in the cache.
we have only 1GB for memcache altogether and about 3 days after  
launching the site,
240 MB are gone already.

do I have to worry about the stats or is this intended caching- 
behaviour?

thanks,
patrick