By InfoStor staff
The Serial ATA (SATA) disk drive/array interface continues to take the industry by storm due to low cost and high capacity (up to 750GB per drive). According to the Gartner Dataquest research firm, SATA accounted for about a quarter (24.7%) of all multi-user disk drives shipped last year and is expected to account for 26.4% this year. By 2009, Gartner predicts that SATA will account for 30.4% (see figure).
And recent enhancements to SATA drives, sometimes (incorrectly) referred to as “SATA-II” enhancements, have helped the interface shed its former image as a “desktop-only” interface characterized by inferior reliability and low performance. Those features include a 3Gbps (300MBps) transfer rate, native command queuing (NCQ) for increased performance (and to a lesser degree, increased reliability), staggered drive spin-up, port hot-plugging, and port multipliers, which allow connection to as many as 15 devices per host port.
SATA II does not refer to an official version of the SATA specification. (SATA II is the former name of the SATA-IO organization.) The latest version of the SATA specification is called SATA 2.5, and SATA 2.6 is under development. According to the SATA-IO organization (www.sata-io.org), SATA Revision 2.6 will include new cable and connector enhancements, ranging from an internal “slimline” cable and connector for small-form-factor (SFF) devices to an internal micro connector for 1.8-inch drives. Other enhancements include updates in command capabilities (including extensions to NCQ such as NCQ Priority and NCQ Unload). The SATA 2.6 spec is expected to be published within the next month.
Here’s a quick rundown of some SATA-based products that recently went into production shipments:
Adaptec’s 2-port 1220SA and 4-port 1430SA are entry-level SATA RAID controllers that support the PCIe (x1 or x4) interconnect and Adaptec’s HostRAID software (RAID 0, 1, and 10). Features common to both controllers include a low-profile form factor, support for NCQ, Adaptec Storage Manager software, 48-bit logical block address (LBA) support, and support for removable media such as SATA tape drives. MSRP for the 1220SA and 1430SA is $75 and $125, respectively.
LSI Logic’s MegaRAID SAS 8708ELP and 8888ELP RAID adapters support Serial Attached SCSI (SAS) and SATA drives. Common features include support for RAID 6 and a 667MHz cache.
The PCI Express-compatible 8708ELP has two internal SAS ports and eight SAS/SATA ports for connection of up to 16 drives and supports RAID 0/1/5/10/50/60, 64 logical volumes, up to 32TB LUNs, and 128MB of write cache. The company claims performance of up to 900MBps.
The 8888ELP also supports all RAID levels and up to 240 drives and 256MB of cache. LSI Logic claims performance of more than 1.5GBps.
Also on the SAS-SATA front, Promise Technology’s VTrak E-Class storage subsystems support SAS or SATA drives, and SAS (model VTrak E310s) or Fibre Channel (E310f) host interfaces. The E310s comes with dual 4x SAS host ports, and the E310f comes with dual 4Gbps Fibre Channel host ports. Both 2U arrays have 12 drive bays, support virtually all RAID levels, and can be expanded with JBOD arrays for up to 60 drives.
For more information on products that support both SAS and SATA drives, see “SAS: The new kid on the I/O block,” InfoStor, January 2007, p. 24.
Infortrend’s EonStor A16F-R2431 is a 16-bay, dual-controller subsystem with two Fibre Channel host interfaces per controller and SATA disk connections. The array is based on the company’s 400MHz ASIC400 chip and supports RAID 6 (dual-parity RAID) and all other RAID levels. Infortrend claims performance of 779MBps with sequential reads and 462MBps with sequential writes.
Arena Maxtronic’s Linux-based Orion 820SR is a NAS device based on a 2GHz Celeron processor, eight SATA drive bays, and two Gigabit Ethernet connections. The Orion 820SR supports RAID 0/1/3/5 (and JBOD), Windows/Linux/Mac platforms, Active Directory Service (ADS) and NT Domain Controller, 512MB of RAM, and single volumes up to 16TB.
AMCC claims that its 3ware 9650SE SATA RAID controller virtually eliminates the write penalty associated with RAID 6. The company also claims a sustained write performance of more than 600MBps and a read performance of more than 700MBps in a 16-drive configuration. The 3Gbps controllers are available with 2 to 24 ports and support the PCIe host interface. The 4-port and 16-port controllers are priced at $395 and $995, respectively.
Enhance Technology is shipping a variety of SATA subsystems under the EnhanceRAID product line. The 1U R4 supports four SATA drives and an Ultra320 SCSI host interface, all RAID levels and JBOD, and online volume expansion, and includes a 500MHz Intel IOP80331 processor. The R4SA supports four SATA drives (for up to 3TB of capacity), RAID 0/10/5/5S, an external SATA (eSATA) port, and automatic drive rebuild. The R4UF also supports four SATA drives and RAID 0/10/5/5S, as well as USB or FireWire 400/800 host ports.
FC + SATA
iQstor Networks’ iQ2880 storage system has 4Gbps Fibre Channel host connections coupled with Fibre Channel and/or SATA disk drives via an FC-to-SATA bridge module. Each iQ2880 supports up to 15 drives, providing 4.5TB of capacity using 300GB Fibre Channel drives or 11.25TB with 750GB SATA drives. A 1.2TB configuration with volume manager-based virtualization software is priced from $12,995. Other available software tools include snapshots, mirroring, replication, provisioning, and policy management.
Intradyn recently began shipments of two new models in its ComplianceVault eSeries line of “all-in-one” e-mail archiving and retrieval appliances, which are based on SATA drives. The appliances come in capacities of 1.5TB (model e1500) and 3.7TB (e3700). The products support RAID 5 and include integrated AIT tape libraries with WORM functionality. The ComplianceVault eSeries systems capture all e-mails on a continuous, real-time basis and store the e-mails on both disk and tape.
The e1500 and e3700 are priced from $14,995 and $29,995, respectively. A clustered configuration, which will support up to 30TB of capacity, is due in the next month or two.