LSI SandForce® DuraWrite™ architecture reduces the amount of data written to the NAND flash memory inside solid state drives (SSDs) for longer effective endurance and higher performance. Storing less data also creates additional free space for dynamic over-provisioning, generating even more improvements. These innovations lower the total cost of ​ownership in both enterprise and client applications.


DuraWrite Architecture Benefits



Fewer Program/Erase (P/E) Cycles

After writing to a block of flash memory, it must be erased prior to writing new data, a procedure known as a program/erase cycle. Since the longevity of solid state drives is related to the cumulative number of P/E cycles, writing less data extends SSD life by decreasing wear on the NAND flash memory.


Faster Reads and Writes

DuraWrite architecture reduces the amount of data before writing it to flash memory. With less actual data to read and write, I/O operations require less bandwidth resulting in higher performance.


More Efficient Garbage Collection

Solid state drives perform periodic clean-up of flash memory blocks containing deleted information, a process called garbage collection. DuraWrite architecture uses less space for data thus creating space for additional dynamic over-provisioning, enabling garbage collection to operate much more efficiently and to take much less time. Since garbage collection shares I/O bandwidth with read and write requests from the user, faster garbage collection translates into higher performance.


Reduced Write Amplification

More free space for additional dynamic over-provisioning enables garbage collection to operate with far fewer data movements. Less data movement reduces write amplification, which increases SSD life.



Impact of Data Entropy

The degree of benefit from DuraWrite architecture depends on the degree of entropy, or randomness, in the underlying data. Low entropy data offers more potential for data reduction, and will see greater benefits from DuraWrite architecture. For typical workloads DuraWrite architecture can reduce data by 50% or more*, yielding a write amplification of less than 1.0. In contrast, without a data reduction technology such as DuraWrite architecture, write amplification by definition must be more than 1.0.


Impact of Data Entropy




Reducing the amount of data stored on flash offers tremendous endurance, performance and cost benefits. These benefits span myriad solid state storage applications, and LSI DuraWrite architecture is a robust and proven solution in both client computing and enterprise applications, such as hyperscale datacenters.


* Source: LSI internal testing