Processing cache miss rates to determine memory space to add to an active cache to reduce a cache miss rate for the active cache

A system coupled to a storage having tracks, comprising:

• a processor;
• an active cache implemented in at least one memory device;
• and
• a computer readable storage medium having computer program code that in response to being executed by the processor performs operations, the operations comprising:
• indicating tracks in the active cache in an active cache list;
• during caching operations to the active cache, gathering information on an active cache miss rate based on a rate of access to tracks that are not indicated in the active cache list over time and a cache demote rate based on a rate of an amount of data removed from the active cache over time;
• determining whether the active cache miss rate exceeds the cache demote rate;
• determining whether adding additional memory space to the active cache would result in the active cache miss rate being less than the cache demote rate in response to determining that the active cache miss rate exceeds the cache demote rate;
• and
• generating a message to a user of the system indicating to add the additional memory space to the active cache in response to determining that adding the additional memory space would result in the active cache miss rate being less than the cache demote rate.

A method for managing an active cache in a computer system to cache tracks stored in a storage, comprising:

• indicating tracks in the active cache in an active cache list;
• during caching operations to the active cache, gathering information on an active cache miss rate based on a rate of access to tracks that are not indicated in the active cache list over time and a cache demote rate based on a rate of an amount of data removed from the active cache over time;
• determining whether the active cache miss rate exceeds the cache demote rate;
• determining whether adding additional memory space to the active cache would result in the active cache miss rate being less than the cache demote rate in response to determining that the active cache miss rate exceeds the cache demote rate;
• and
• generating a message to a user of the computer system indicating to add the additional memory space to the active cache in response to determining that adding the additional memory space would result in the active cache miss rate being less than the cache demote rate.