Memory space management for object-based memory system

A method for pre-allocating memory for object-based cache data is provided in which request for an object having an associated property parameter that defines the memory requirements for the object. In response, a table of allocation buckets is searched for a bucket having the associated property parameter that can at least meet the memory requirements for the requested object. If an object identifier (OID), having a previously allocated physical address in main memory, is identified in the table of allocation buckets then the identified OID is assigned to the object. The object is stored in the object cache with the assigned OID, and the OID is removed from the bucket. Also included is a table of allocation buckets in a computer system in which each of a plurality of buckets is capable of holding object identifiers (OIDs). Each object identifier (OID) has a pre-allocated physical memory, with buckets of the table of allocation buckets being replenished by recycling a previously used OID when the object associated with the OID is reclaimed.