1
Abstract.............................................................................................................................................. 2
Introduction......................................................................................................................................... 2
Categories of server disk drives............................................................................................................. 2
Characteristics of disk drives................................................................................................................. 3
Small form factor and large form factor disk drives .............................................................................. 3
Disk drive capacity........................................................................................................................... 4
Disk drive performance..................................................................................................................... 4
Reliability........................................................................................................................................ 5
Drive qualification process.................................................................................................................... 6
Interconnect technology........................................................................................................................ 7
Serial Attached SCSI (SAS) ............................................................................................................... 7
SAS-2 ............................................................................................................................................. 8
Second generation Serial ATA (SATA)................................................................................................ 8
Interconnect bandwidths and drive throughput..................................................................................... 8
Improved performance and reliability with RAID...................................................................................... 9
Advanced controllers ........................................................................................................................... 9
Solid state drives for servers.................................................................................................................. 9
HP solid state drive reliability requirements........................................................................................ 10
NAND over provisioning and wear-levelling.................................................................................. 10
Power loss protection .................................................................................................................. 10
Value, mainstream and performance SSDs........................................................................................ 11
SSD performance........................................................................................................................... 12
Conclusion........................................................................................................................................ 12
For more information.......................................................................................................................... 13
Call to action .................................................................................................................................... 13
Drive technology overview
technology brief, 3
nd
edition