My suspicion is some problem here: store_dir_select_algorithm least-load # cache_dir aufs /mnt/cachedrive1 1342177 128 512 cache_dir aufs /mnt/cachedrive2 1426227 128 512 cache_dir aufs /mnt/cachedrive3 1426227 128 512 cache_dir aufs /mnt/cachedrive4 1426227 128 512 cache_dir aufs /mnt/cachedrive5 427008 128 256 Not knowing internal processing within squid in this scenario, but theoritically there MIGHT be the risk, having the same object cached up to 4 times, because all cache_dir have equal storage properties. Which reduces overall sum of cachable objects significantly. And MIGHT lead to unnecessary purge of cached objects, in case a cache_dir almost full. So I would either use just one large cache_dir (which might then run into the limit regarding max. number of cachable objects in one dir 2**24) or (better solution) set disjunct limits on the size of cachable objects for the various cache_dir, using cache_dir aufs /mnt/cachedrive2 1426227 128 512 min-size=xxxx max-size=xxxx And move these lines minimum_object_size 16 KB maximum_object_size 512 MB on top of this one: maximum_object_size_in_memory 300 KB -- View this message in context: http://squid-web-proxy-cache.1019090.n4.nabble.com/Extremely-Low-Request-Hit-Ratio-tp4661495p4661504.html Sent from the Squid - Users mailing list archive at Nabble.com.