proxy_cache fills harddrive despite max_size being set

[W-Mark Kubacki]

Hello.

In Nginx 0.8.38 (and later; on amd64) I've set this:
  proxy_cache_path /var/tmp/nginx/cache levels=1:2
keys_zone=my-cache:10m inactive=8h max_size=100m;

Using that cache Nginx fills my harddrive with its cache, ignoring max_size.

Did somebody else observed that behaviour? Or, did I something wrong?

-- 
Thanks für your help in advance!
Mark
http://mark.ossdl.de/