Avago Technologies MegaRAID Fast Path Software - Manual (Page 15)

LSI Corporation Confidential | July 2011 Page 15
MegaRAID SAS Software User Guide Chapter 1: Overview | Serial ATA III Features
1.3 Serial ATA III Features The SATA bus is a high-speed, internal bus that provides a low pin count (LPC), low
voltage level bus for device connections between a host controller and a SATA device.
The following list describes the SATA III features of the RAID controllers:
 Supports SATA III data transfers of 6Gb/s
 Supports STP data transfers of 6Gb/s
 Provides a serial, point-to-point storage interface
 Simplifies cabling between devices
 Eliminates the master-slave construction used in parallel ATA
 Allows addressing of multiple SATA II targets through an expander
 Allows multiple initiators to address a single target (in a fail-over configuration)
through an expander
1.4 Solid State Drive Features The MegaRAID firmware supports the use of SSDs as standard drives and/or additional
controller cache, referred to as CacheCade 2.0 SSD Read Caching software. SSD drives
are expected to behave like SATA or SAS HDDs except for the following:
 High random read speed (because there is no read-write head to move)
 High performance-to-power ratio, as these drives have very low power
consumption compared to HDDs
 Low latency
 High mechanical reliability
 Lower weight and size
NOTE: Support for SATA SSD drives applies only to those drives that support ATA-8 ACS
compliance.
You can choose whether to allow a virtual drive to consist of both CacheCade 2.0 SSD
Read Caching software devices and HDDs. For a virtual drive that consists of CacheCade
2.0 SSD Read Caching software only, you can choose whether to allow SAS CacheCade
2.0 SSD Read Caching software drives and SATA CacheCade 2.0 SSD Read Caching
software drives in that virtual drive. For virtual drives that have both CacheCade 2.0 SSD
Read Caching software and HDDs, you can choose whether to mix SAS and SATA HDD
drives with SAS and SATA CacheCade 2.0 SSD Read Caching software devices in various
combinations.l
NOTE: Support for SATA SDD drives applies only to those drives that support ATA-8 ACS
compliance.