EMC: Netto / Raw Capacity of an EMC disk
Problem description:
As a DBA, System Archtitect or Engineer you are sometimes faced to create the storage layout for database systems. In order to get a detailed picture on how much capacity is available for your system, you have to calculate the netto capacity for your RAID-Level. Unfortunately EMC disks do not provide the same capacity as they are labeled with (independent of the used RAID-Level). In order to calculate the right capacity for your RAID-Level, you have to calculate with the raw capacity of an EMC disk.
Problem resolution:
Below you can find a table of EMC Clariion disks and their actual raw capacity:
| Disk Size | Raw / Usable Capacity |
|---|---|
| 73 GB | 66.61 GB |
| 146 GB | 133.65 GB |
| 250 GB | 230.13 GB |
| 300 GB | 268.37 GB |
| 320 GB | 297.01 GB |
| 400 GB | 366.76 GB |
| 450 GB | 402.57 GB |
| 500 GB | 458.56 GB |
| 750 GB | 687.86 GB |
| 1 TB | 917.15 GB |
