Press release
SanDisk Also Proposes Two Metrics for End-Users to Measure Performance and Endurance: virtualRPM (vRPM) and Long-Term Data Endurance (LDE)
- ExtremeFFSTM greatly accelerates SSD random write speeds and endurance
- vRPM allows consumers to measure and compare SSD and hard disk drive performance
- Industry encouraged to adopt a simple endurance metric to determine the lifespan of an SSD
LONDON, UK, Nov. 5, 2008 - SanDisk® Corporation (NASDAQ: SNDK) today unveiled an advanced flash file system for solid-state drives (SSDs) that yields dramatic improvement in performance and reliability for computing applications. Called ExtremeFFSTM, this next-generation patented flash management system - which has the potential to accelerate random write speeds by up to 100 times over existing systems - will ship in SanDisk products during 2009.
Speaking in Los Angeles at WinHEC 2008, Rich Heye, senior vice president and general manager for SanDisk's Solid-State Drive (SSD) Business Unit, presented ExtremeFFS along with two metrics - vRPM and LDE - that can help end-users evaluate SSDs. vRPM enables comparisons in performance between an SSD and a hard disk drive (HDD) or another SSD, and LDE calculates the lifespan of a solid-state drive.
For SSDs to perform optimally in Windows Vista, and thus replicate or surpass the functionality of hard disk drives, a new flash management technology is needed to accelerate SSD write speed and endurance, he said. "SSDs will revolutionize client storage, but we need new benchmarks that allow them to be treated differently than HDDs."
In 1994 SanDisk introduced TrueFFSTM, which has been the leading flash file system for major mobile handset vendors. TrueFFS was incorporated into one previous version of Windows, as the PCMCIA FTL of choice for its performance, scalability and low overhead. When using an SSD under Windows Vista, the demands on the SSD require a large quantity of random writes, as opposed to sequential access. "The mismatch to block size is significant," said Heye.
Enter Extreme FFS
To maximize random write performance, SanDisk developed the ExtremeFFS flash file management system. This operates on a page-based algorithm, which means there is no fixed coupling between physical and logical location. When a sector of data is written, the SSD puts it where it is most convenient and efficient. The result is an improvement in random write performance - by up to 100 times - as well as in overall endurance.
ExtremeFFS incorporates a fully non-blocking architecture in which all of the NAND channels can behave independently, with some reading while others are writing and garbage collecting. Another key element of ExtremeFFS is usage-based content localization, which allows the advanced flash management system to "learn" user patterns and over time localize data to maximize the product's performance and endurance. "This feature might not show up in benchmarks, but we believe it is the right thing to do for end-users," Heye said.
