Patent ID: 7177853

Claim:
A method for cache management within a data storage system comprising: associating a tag with each portion of a shared memory, said tag indicating availability of said each portion for use; and performing processing by a first process to obtain a first portion of said shared memory, said processing including: making an initial determination, using a first tag associated with said first portion, as to whether said first portion is available or not available; if said initial determination indicates that said first portion is available, subsequently determining whether said first tag has been modified since said initial determination, wherein if said subsequently determining determines that said first tag has been modified, said first portion has been granted to another process since said initial determination of availability and said first portion is not available, and if said subsequently determining determines that said first tag has not been modified, said first portion has not been granted to said another process since said initial determination of availability and is currently available, said another process also performing said processing to obtain a portion of said shared memory; and if said initial determination indicates that said first portion is available and said subsequently determining determines that said first tag has not been modified since said initial determination, updating said first tag to indicate that said first portion associated with said first tag is not available and that said first portion is being granted for said first process, wherein said subsequently determining and said updating are atomically performed.