In response to a cache flush event indicating that host data accumulated in a cache of a storage processor of a data storage system is to be flushed to a lower deck file system, an aggregation set of blocks is formed within the cache, and a digest calculation group is selected from within the aggregation set. Hardware vector processing logic is caused to simultaneously calculate crypto-digests from the blocks in the digest calculation group. If one of the resulting crypto-digests matches a previously generated crypto-digest, deduplication is performed that i) causes the lower deck file system to indicate the block of data from which the previously generated crypto-digest was generated and ii) discards the block that corresponds to the matching crypto-digest. Objects required by a digest generation component may be allocated in a just in time manner to avoid having to manage a pool of pre-allocated objects.