LSI, three letters that are probably etched on nearly every hard drive controller you've ever owned, as of yesterday emblazon 10 more controllers of SAS, SATA and SSD storage devices. On Jan. 19, the company unveiled a series of new RAID controllers and host bus adapters that double the bandwidth to 6GB/s of four of its MegaRAID cards, increase the number of controllable hard drives to 1024, and deliver a sustained read and write performance for applications that require sequential storage such as video streaming and genomic research as seen in this LSI promotional video.
Cache is King
The LSI 3ware 9750 is a new family of 6Gb/s SATA and SAS RAID-on-chip controllers. The cache on these boards is backed up by an on-board battery, which according to Tom Kodet, LSI's worldwide channel product marketing manager, provides an important measure of data security. "What if data was written on cache and the server locked up or failed? How does one preserve the data in cache?" With most RAID controllers, you don't, and whatever was waiting to be written is lost. And if your application was streaming surveillance video, "those last two seconds of video could be the the most interesting," he said, perhaps revealing what caused the crash in the first place. "With battery-backed cache, the board can be removed with the battery, preserving the data in the cache. When you plug it in to a new server, it will resume writing data from the cache," Kodet said.
LSI's 3ware 9750 series are rated to deliver a 2.5Gb/s transfer rate for sequential reads, 1.1Gb/s for sequential writes, work with older boards, and are available in 4- and 8-port configurations starting at US$385. New MegaRAID series SATA/SAS controller cards are also now available with a 6GB/s interface starting at $229. MegaRAID comes in four- or eight-port configurations for internal or internal/external applications. And the LSI line of HBAs include the SAS 9200-16e, a 16-port SATA/SAS board that can handle as many as 1024 physical devices.