Patent ID: 7606807

Claim:
A storage system comprising: a global cache to store resources for servicing requests issued from one or more processes at the same time; a free cache to receive resources from the global cache and to store the received resources as free resources; a plurality of local caches, wherein each of the plurality of local caches is configured to receive free resources from the free cache, wherein the received free resources in each of the plurality of local caches can be accessed exclusively by a single process at one time; and a buffer cache manager to manage reallocating resources from the global cache to the free cache and from the free cache to a local cache, wherein the resources include a buffer, and wherein the buffer cache manager comprises: a pre-allocator to pre-allocate resources necessary to service a request by determining whether the necessary resources are present in the local cache and, if the necessary resources are not present in the local cache, attempting to transfer some resources from the free cache to the local cache; a refill component to transfer some resources from the global cache to the free cache if the amount of resources in the free cache is below a watermark; and a reservation counter to keep track of an amount of resources in the free cache that is reserved for transfer to a local cache.