3Gbps host controllers set to go

Marvell Semiconductor Inc. will get a jump on next-generation serial ATA designs when it announced that it is sampling 3Gbps host controllers. Once hard-disk drives based on Sata II emerge early next year, the Sata II controllers aim to enable the faster and more robust set of mid- and low-end servers and arrays that are expected to support the second-generation standard.
The 88SX60X1 host controllers are four- and eight-port devices that double the data rate of the first-generation 1.5Gbps devices. They also implement Sata II native command queuing for lower latency on random drive accesses as well as port multiplier capability for connecting up to 16 drives per controller port.

The new capabilities will bolster the profile of low-end and midrange servers and arrays now adopting the Sata interface. "With the SCSI-like manageability and the higher data rates, you can create a new segment of the storage array market," said John Williams, product-marketing manager for Marvell.

Williams said the market for JBOD (just a bunch of disks) systems directly attached to servers over about 3m or less of Sata cabling is rapidly declining. However, the market for low-cost arrays linked to a Fibre Channel external network but using lower-cost internal Sata drives on an internal Sata backplane is on the rise.

The Marvell devices link to a 64-bit, 133MHz PCI-X host bus. Future versions will link to PCI Express and will support the upcoming 3Gbps Serial Attached SCSI standard.

Marvell also plans to develop controllers sporting up to 16 ports as well as more integrated variants that may tap into the company's intellectual property in Fibre Channel, iSCSI, and disk and array controllers.

Williams said that he expects the first hard-disk drives implementing a 1.5Gbps version of the Sata II interface will emerge early next year, followed in one or two quarters by drives that implement the full 3Gbps data rate.

The host controllers will be in production in the fourth quarter of 2003.