Storage Basics: Choosing a RAID Controller Page 2


Want the latest storage insights?

Download the authoritative guide: Enterprise Data Storage 2018: Optimizing Your Storage Infrastructure

Continued from Page 1

Internal Host-Based

Internal host-based RAID technology is divided into two camps: Serial ATA (SATA) and SCSI. Choosing between them involves a trade off of speed vs. price, as SCSI is faster, but more expensive.

"From a price perspective, the delta between SCSI and SATA drives is over 5x for a comparably sized drive," states Barbara Murphy, vice president of marketing for Applied Micro Circuits Corp.'s storage business unit.

AMCC, which completed the purchase of RAID management tools vendor 3ware last month, claims 3ware's recently unveiled Escalade 9000 SATA RAID controllers bring SATA speeds closer to enterprise level, at least for certain applications. "For applications that have a high degree of sequential I/O (disk backup, streaming video, image capture)," Murphy says, "the 3ware 9000 series controllers with SATA drives will outperform any other SCSI or SATA controller on the market."

Frugality has its limits though. "We would not suggest that you put a Serial ATA disk in a situation where it's a highly transaction-oriented, high-performance, critical application environment," cautions Cox. However, "as people get more experienced with Serial ATA technology, you're going to hear 'Whoa, holy cow, you know, I can buy this stuff a lot cheaper.'"

This may be bad news for vendors, as SCSI and Fibre Channel drives carry a higher gross margin than do ATA drives, according to Cox, who adds that they "would have to sell a lot more units in order to keep their revenue up and, more importantly, to keep their gross margin up."

Another player in the SATA market is Intel. In early 2003, Intel began selling a four-port SRCS14L controller. The product tightly integrates the RAID controller with the server architecture. "So instead of just saying, 'Go and shop for the motherboard and for the RAID card that suits your needs, and then, it's up to you to make sure that it all works together,' we say, 'If it's on our list as a validated combination, then you can be very confident that it's a robust solution,'" says Steve Fingerhut, Intel product line manager for volume products marketing.

The adoption of the speedier SATA II standard may bring another ball to SATA's court. "SATA will [occupy] a stronger market position as SATA II features arrive," says Luca Bert, director of product & programs management, RAID storage adapters for LSI Logic. "With [features] such as native command queuing, enclosure management, and port multiplier support, SATA II will be a viable solution for an enterprise-level server, especially in the cost sensitive segment."

Page 3: External Host-Based and Controller-Based RAID

Submit a Comment


People are discussing this article with 0 comment(s)