Usable Remaining Capacity is the amount of storage that is available to the customer AFTER workloads, RF, storage savings are applied. It represents what they should have remaining once deployed.
Sizer presents the values in both RF2 and RF3.
Usable Remaining Capacity (Assumming RF2)
- HDD Usable Remaining Capacity = (Raw + Compression Savings + Dedupe Savings + ECX Savings – Workload – RF Overhead – CVM overhead ) / 2
- SSD Usable Remaining Capacity = (Raw + Compression Savings + Dedupe Savings + ECX Savings – Workload – RF Overhead – CVM overhead + Oplog ) / 2
- Notes:
- Usable capacity is basically RAW + storage savings with data reduction techniques like compression less workload, RF overhead and CVM overhead.
- If All Flash, Compression Savings, Dedupe Savings , ECX Savings, RF Overhead, and CVM overhead that would be attributed to HDD’s is applied to SSDs
- For SSD Capacity, Oplog is included as part of CVM overhead for SSDs but also added back as it is a Write log and so is available for user data.