Texas Memory Systems (TMS) has responded to cheaper flash-memory-based solid state drive competition for its DRAM-based RamSan by introducing its own flash product. But it has also added a DRAM cache to make it perform faster.

The RamSan is a solid state drive (SSD) using DRAM chips to provide very high performance, up to 400,000 IOPS, for applications such as Echelon that need the very highest performance. RamSan is expensive compared to equivalent capacity hard drive arrays and, latterly slower flash-memory SSDs.

Mtron, Samsung, SanDisk and others have introduced 32GB flash SSD drives with 64GB ones coming. These can be built up into SSD arrays costing much less than a similar capacity RamSan and, at ratings of thousands of IOPS, strongly outperforming hard drives with their several hundred IOPS.

TMS has introduced its RamSan-500 with one or two terabytes of total capacity, the bulk of which is NAND flash front-ended with a DRAM cache. The unit is inside a 4U-high rack enclosure. Frequently-accessed data is held in the cache and this lifts the overall performance to 100,00 random I/O reads a second. The random write performance, not accelerated by the cache is a relatively slow 10,000 IOPS. This makes it the fastest-flash-based SSD available.

DRAM caching is used by DTS to accelerate its hard drive and by Gear6 to accelerate network-attached storage (NAS).

The RamSan-500 can be SAN-attached with up to eight 4Gbit/s Fibre Channel ports. Several RamSan-500s can be combined to deliver more capacity.

TMS makes the point that, compared to a similar capacity high-end hard disk-based RAID system, the RamSan-500 delivers more than sixteen times the performance while drawing a third less power.

Woody Hutsell, EVP at TMS, said: "With the RamSan-500 we have engineered a solid state disk system that uniquely capitalizes on the best attributes of both (DRAM) and flash, at a price point that we think will be attractive to customers who might otherwise (use) HDD-based arrays, that offer lower performance and higher power consumption."

Detailed pricing was not revealed.