FlashSystem Sizing: Why Usable Capacity Beats Raw TB
Raw TB is a hardware number. Usable TB is an application planning number. Effective TB is a data reduction assumption. Protected TB is what remains after snapshots, Safeguarded Copy, replication, and recovery copies are considered.
Capacity comparison discipline
| Capacity View | Use It For |
|---|---|
| Raw | Media inventory and hardware bill of material. |
| Usable | Application placement and growth planning. |
| Effective | Compression and deduplication economics after workload validation. |
| Protected | Real recovery architecture, including copy retention and replication. |
For the checklist version, see FlashSystem Sizing and Usable Capacity.
Sources
Related Directory Entries
IBM FlashSystem 5600
Current-generation 1U NVMe FlashSystem for smaller mixed workloads, compact OLTP, IBM Power attachment, edge deployments, and buyers who need a serious array without jumping to the 7600 tier.
IBM FlashSystem C200
Capacity-optimized FlashSystem for backup, sequential, archive, media, and cost-sensitive high-capacity workloads where flash density and durability matter.
IBM FlashSystem 5300
High-interest 1U NVMe FlashSystem still generating warehouse exposure, especially around 20 TB to 30 TB environments, datasheets, control enclosures, and refresh questions.