The evolution of the storage world
Storage-related technologies have been changing really fast in recent years and flash memory is totally redefining the storage offering, both in the architectures, as described previously, and also on the effective components where data is stored.
Spinning disks
Just 10 years ago (but we could also say just a little over 5 years ago), the different tiers described previously were usually filled with the following types of storage:
- Tier 0: 15K RPM Serial-Attached SCSI (SAS) disks
- Tier 1: 10K RPM SAS disks
- Tier 2: 7K RPM SATA or nearline disks
- Tier 3: Usually tapes
Traditional Hard Disk Drives (HDD) were the standard components for storage arrays, and more were used both for redundancy and for increasing performance. RAID hardware was the standard at the beginning, surpassed by a more software controlled style of data management.
The typical interface and bus for those hard disks is SAS, working at 6 or 12 Gbps. SATA disks use the Serial ATA (3.0 revision works at...