Violin adds MLC flash to SSD RAID arrays

By Dave Simpson

Violin Memory today announced the 3140 Capacity Flash Memory Array, a RAID array based on solid-state disk (SSD) drives with multi-level cell (MLC) NAND flash technology. The 3140 is an addition to Violin Memory’s 3200 series of SSD RAID arrays, which are based on single-level cell (SLC) NAND flash.

According to Don Basile, Violin Memory’s CEO, the SLC-based 3200 arrays provide 2X the performance of the MLC-based 3140, while the 3140 provides 4X the capacity of the 3100 series in the same form factor. In terms of latency, the 3140 is spec’d at 400 microseconds, while the 3200 series is spec’d at 100 microseconds.

The 3U 3140 SSD holds 40TB (30TB of usable capacity in a RAID configuration), or 500TB per rack, which is about 5X the density of RAID arrays based on traditional hard disk drives. The company claims performance of up to two million I/Os per second (IOPS) per rack, assuming 4KB blocks and a 70/30 read/write ratio.

The 3140 SSD is priced at $650,000 in a 40TB configuration, which translates into about $16 per GB or $3 per IOPS. The $16-per-GB price point is on par with high-end RAID arrays based on conventional (rotating) hard disk drives.

The SSDs can be direct attached via a PCI-Express bus, or LAN/SAN-attached via 10GbE or Fibre Channel (4Gbps or 8Gbps).

The 3140 is based on the same platform and technologies as the 3200 series, including switched memory, caching and network translation technologies, but the two lines differ in the intelligent memory modules and aggregation techniques used for the different NAND flash technologies (MLC and SLC).

Both the 3140 and 3200 series have five-year lifetimes, although the company does not recommend more than a 90% write load on the 3140. “Theoretically, you could write 40TB per day for five years on the 3140,” says Basile.

Toshiba is Violin Memory’s primary NAND flash supplier. (Toshiba is also one of the investors in Violin Memory.)

Violin’s addition of MLC-based devices to its line of SSDs is indicative of the general trend toward MLC NAND flash in enterprise disk arrays (see “MLC vs. SLC for enterprise SSDs”).

“MLC will become dominant very quickly,” says Basile. “We expect MLC vs. SLC shipments to be in the 70/30 to 90/10 range. Longer term, in about two years, you’ll see MLC and SLC SSDs blended together in single arrays.”

Violin demonstrated the 3140 at this week’s Oracle Open World conference. The SSD is sampling now, with production shipments slated for the fourth quarter.

Related articles:

Violin SSD array hits price parity with HDD arrays

Violin to acquire Gear6 for caching software

Pliant adds MLC SSDs to Lightning lineup

This article was originally published on September 20, 2010