Increasing SSD Performance and Lifetime with Multi-stream Technology

NAND Flash Solid-State Drives(SSDs) are increasingly deployed because of their high IOPS performance and low power consumption. However, one SSD drawback is that, as a SSD continually writes data, valid data can fragment across the NAND flash medium. To reclaim space within data storage blocks containing invalid (obsoleted) data, Garbage Collection activity first relocates valid data to other data blocks and then completely erases the original data blocks. Garbage Collection decreases performance and increases Write Amplification. With multi-stream recently adopted as a T10 SCSI standard, Garbage Collection can be completely eliminated or reduced by storing associated (similar update frequency) data in the same data block. This helps avoid NAND Flash erase block fragmentation for data having the same update frequency. As a result of the decreased write amplification, storage systems exhibit improved read/write performance and longer SSD device lifetimes when exploiting multi-stream methods. Learning Objectives Multi-stream concepts and operation Understanding multi-stream benefits (improved performance and lifetime of SSD) Data center application use cases