Always monitor your cache hit ratio using ssacli or HPE OneView after installation. If you are seeing less than 50% cache hits, consider increasing the size of your SSD cache or adjusting your workload pattern.
This is a software-enforced tiering feature. Without the key, the SSDs connected to your controller will function only as standard standalone drives or part of a traditional RAID volume. They will not act as a cache for other drives. You might wonder, "Why not just buy an all-SSD array?" The answer is cost versus capacity . A 10TB SSD array is exponentially more expensive than a 10TB HDD array. Smart Cache offers a sweet spot. Hpe Smart Cache License Key
The HPE Smart Cache License Key is not merely a software unlock; it is a performance multiplier. For a relatively small upfront cost (license + one or two small SSDs), you can breathe new life into legacy HDD arrays, drastically reducing read latency and increasing throughput. Always monitor your cache hit ratio using ssacli