Described are examples for storing, in a first zone cache (110), one or more logical blocks (LBs) corresponding to a data chunk, writing, for each LB in the data chunk, a cache element of a cache entry (210) that points to the LB in the first zone cache (110), where the cache entry (210) includes multiple cache elements corresponding to the multiple LBs of the data chunk, writing, for the cache entry (210), a table entry in a mapping table (108) that points to the cache entry (210), and when a storage policy is triggered for the cache entry, writing the multiple LBs, pointed to by each cache element of the cache entry (210), as contiguous LBs in an isolation block for the data chunk in a second zone stream (114), and updating the table entry to point to the isolation block in the second zone stream (114).