SAS storage will not die out, the new generation of 24G+ SAS standard is officially released

July 25 news, although solid-state drives are gradually turning to the PCIe physical interface using the NVMe protocol, many applications still rely on SCSI (SAS) technology.

On Wednesday local time, the SNIA SCSI Trade Association Forum (STA) and the INCITS/SCSI standards organization launched a 24G+ SAS specification specifically for next-generation hyperscale data center HDDs and SSDs, indicating that SAS will continue to develop.

The SAS speed specification was upgraded to 2.4 GB/s in 2020, and products equipped with this interface are currently available. The new 24G+ standard maintains this speed but adds five new features designed to enhance storage performance in traditional servers and hyperscale data centers.

“24G+ SAS is a major advancement for our industry and continues to demonstrate the value of SAS technology in the broader data storage space,” said Cameron T. Brett, Chairman of the Board of Directors of the SNIA STA Forum. “These key features span both hard disk drives and solid state drives and benefit hyperscale data centers as well as traditional servers and storage. SAS and SCSI have been around for more than 30 years, providing data centers with high performance, reliability and scalability, and 24G+ SAS takes data storage to the next level.”

It is reported that 24G+ SAS introduces the command duration limit (CDL) function to control HDD latency to ensure that operations can be completed within the specified time, thereby ensuring efficiency and reliability in large data environments.

On the other hand, the latest standard also introduces a “format preset” function related to HDDs, which simplifies the management process of CMR and SMR HDDs and is expected to further reduce the number of SKUs in the data center.

The third HDD-specific feature is called "Logical Depopulation," which is designed to identify and remove "bad drives" from data sets in very large-scale applications.

24G+ SAS also introduces a “Rebuild Assist” feature for SSDs that helps identify unreadable partitions that need to be rebuilt from another source.

Finally, 24G+ SAS also supports a “persistent link” feature that optimizes performance by remaining open, eliminating the losses associated with repeated switching (ideal for high-performance SSDs).