By Dave Simpson
Seagate typically introduces disk drives one at a time, but the company broke from that tradition today with the biggest launch of enterprise-class drives in the company’s history. Seagate announced two solid-state disk (SSD) devices in its Pulsar line, two hard disk drives (HDDs) in the Savvio family, and a capacity-optimized drive in the Constellation product family.
Representing the second generation of Seagate’s SSD drives (the first generation shipped only to select OEMs), the company introduced the Pulsar.2 SSD and the Pulsar XT.2 SSD.
The Pulsar.2 is Seagate’s first enterprise-class SSD based on multi-level cell (MLC) NAND flash technology, which is significantly less expensive than single-level cell (SLC) NAND technology. (Pricing varies widely, but the price differential between MLC and SLC is currently about 3.5:1.) The Pulsar.2 is available with either 6Gbps SAS or 6Gbps SATA interfaces. Capacity ranges from 100GB to 800GB.
Until recently, the primary drawback to MLC-based SSDs was a relative lack of endurance, or reliability. To achieve enterprise-class endurance, Seagate uses a number of controller-based techniques on the Pulsar.2 SSDs. According to Rich Vignes, Seagate’s senior product line manager for SSDs, those techniques include error detection and correction, media management (e.g., wear leveling, “garbage collection” and bad block management), and signal processing.
Seagate claims that that the Pulsar.2 SSDs can endure more than 10 full writes per day. On a 400GB device, that translates into 4TB per day. The company also claims that the SSDs can withstand 15,000TB of writes over the lifetime of the drives. (The SSDs come with a three-year warranty.)
Company officials did not disclose performance figures for the Pulsar.2 SSDs, which are currently being tested.
The new Pulsar SSDs are the first results of a partnership with Samsung that Seagate announced last August.
The 2.5-inch Pulsar XT.2 SSD is based on SLC NAND technology, with capacity ranging up to 400GB. The Pulsar XT.2 is available only with a 6Gbps SAS interface.
The Pulsar XT.2 SSD is the fastest drive in Seagate’s portfolio. The company claims sustainable performance of up to 48,000 I/Os per second (IOPS) on random reads and 22,000 IOPS on random writes. Maximum throughput is pegged at 360MBps on sequential reads and 300MBps on sequential writes.
Seagate claims that the SLC-based Pulsar XT.2 can handle 25,000TB of writes over the lifetime of the drives. (That compares to 15,000TB for the MLC-based Pulsar.2.)
For both of the SSDs, Seagate claims an annual failure rate (AFR) of 0.44% and an MTBF rating of two million hours. (For an interesting discussion on AFR and MTBF, see the blog post “Diving into MTBF and AFR: Storage Reliability Specs Explained” on Seagate’s site.) The SSDs are in the OEM evaluation stage, and will be available to the channel in the second quarter.
Seagate also announced two new members in its Savvio line of HDDs: the 2.5-inch Savvio 15K.3 and Savvio 10K.5. The company positions these drives as Tier-1 devices (where SSDs represent Tier 0 and capacity-optimized drives comprise Tier 2).
The 10,000rpm Savvio 10K.5 packs up to 900GB in a 2.5-inch small form factor. In addition to the 900GB version, the drives are available in 600GB, 450GB and 300GB capacities. Interface options include 6Gbps SAS or 4Gbps Fibre Channel.
The 2.5-inch 15,000rpm Savvio 15K.3 is a high-performance drive that comes in 300GB or 146GB capacities with 64MB of cache. The Savvio 15K.3 is available only with a 6Gbps SAS interface.
On both of the Savvio drives, Seagate specifies reliability ratings of 0.44% AFR and two million hours MTBF.
The Savvio 10K.5 is shipping to OEMs and the channel today, while availability of the Savvio 15K.3 is slated for the next quarter.
Seagate also introduced the 3TB, 7,200rpm Constellation ES.2, which the company describes as a capacity-optimized nearline drives. The drives are available with 6Gbps SAS or 6Gbps SATA interfaces. Seagate is currently shipping the Constellation ES.2 drives to its OEMs, with shipments to the channel expected in the second quarter.
A new feature introduced with the Constellation ES.2, that will eventually be available with all of Seagate’s enterprise-class drives, is dubbed RAID Rebuild. Company officials claim that RAID Rebuild enables 80% to 85% faster rebuilds, which is particularly important with drives in the 3TB range.
Seagate stuck to its policy of not disclosing MSRP pricing for its enterprise-class drives. End-user pricing is up to the company’s OEMs and channel partners.