Sunnyvale, Calif.If you've ever suffered disk failure, you'll be interested in a new product from Applied Micro Circuits Corp. AMCC is rolling out a battery-backed AMCC StorSave Platform for its line of 3ware 9000 Series RAID (redundant array of inexpensive disks) controllers. The 3ware company is now part of AMCC.
The PCI bus StorSave Platform, priced at about $150, combines firmware and a BBU (battery backup unit), for data protection and SATA (Serial ATA) network storage.
SATA is largely used in mission-critical cluster-computing and super-computing applications where the ability to get data to disk quickly and reliably lets a cluster perform its primary task of crunching numbers.
For its part, SATA is an evolution of the older parallel ATA physical storage interface. SATA replaces the predecessor's 40-pin cable and connector with a 7-pin cable and connector. To your system software, a SATA device is indistinguishable from a legacy UDMA/ATA (ultra direct memory access) device.
Power To Cache
In operation, the PCI bus StorSave board supplies power to a cache memory module in the event of power loss. StorSave includes proprietary features that use a write journaling technique. In a SATA RAID environment, a controller can use both controller and drive-write caching for best performance, while still preventing data loss in the event of a system power failure.
When fully charged, the plug-in's battery preserves the contents of the controller cache memory for up to 72 hours. When power is restored, cached data is then written to the disk array, thereby providing uninterrupted data storage.
In RAID 5 environments without BBU, manufacturers recommend setting controller cache to write-through, and disabling disk caching. This practice mitigates system and drive resets and/or power failures that can put data in disk-cache and controller-cache at risk. However, with cache-off, system performance suffers during standard I/O operations. Disk-cache-off also contributes to lower system performance during RAID 5 degraded mode operations and re-builds.
Addressing that problem, StorSave Platform-enabled products protect data that hasn't been committed to disk media, in both controller and disk caches. The platform claims to enhance performance by enabling disk-cache to remain on during all RAID operations. It also maintains the controller cache setting to write-back.
Other Data Protection Features
The AMCC StorSave Platform includes proprietary data protection features, such as disk drive power-on reset protection, dynamic sector repair, extensive drive timeout recovery, out-of-band signaling retry, and write journaling, in addition to the BBU.
Now what about the 3ware SATA controllers? Based on AMCC's StorSwitch switched RAID architecture, they provide scaleable capacity up to 4.8-Tbytes/controller, using 400-Gbyte drives. Total system capacity is limited only to available PCI bus slots.
The 3ware 9000 Series (click for datasheet), available in 12-port, 8-port, and 4-port configurations, is claimed to deliver "substantial performance increases" over previous 3ware RAID controllers. AMCC's hardware RAID architecture features an on-board processor and an integrated RAID ASIC that offloads RAID controller functions from a host processor, dedicating server processing to its core applications, thus enhancing overall system performance.
AMCC also offers its 12-port and 8-port 3ware 9000 Series controllers with MI (multi-lane internal) connectors; these are for high-capacity industrial environments. This design helps simplify installation and routing via a SATA-approved cabling approach in large-scale configurations.
For more info, contact 3ware, 455 West Maude Avenue, Sunnyvale, Calif. 94085. Phone: 408-523-1000. Fax: 408-523-1001.
Check out 3ware's Web site for additional and related information.