At Computex Taipei 2014, WD, a Western Digital company, is demonstrating its first hard drive with PCI Express (PCIe) support. Technological cooperation with its partners has resulted in the creation of a storage product prototype that uses the SATA Express interface, allowing computers to easily exceed previous performance limits.
With cloud computing and big data technologies advancing and telecoms gearing up for 4G LTE services, terminal data output rates have been increasing. Therefore, it can be anticipated that in tomorrow's digital world, data will be generated faster and users will be more demanding in terms of real-time data transmission. Although front-end access speeds have continued to improve, transmission speeds of the mainstream terminal storage interface SATA has been limited at 550MB/s. If this bottleneck could not be overcome, current and future high-speed applications would continue to be restricted.
The SATA-IO organization spent three years developing the SATA Express specifications, which was announced and introduced in 2013, with a goal to create an environment where PCIe and SATA would co-exist, and the relatively superior bandwidth capabilities of PCIe could be used to enhance the read/write speeds of SATA storage devices. One year after the SATA Express specifications were unveiled, WD and its technology partners have built a corresponding prototype storage product to allow computer manufacturers to adopt SATA Express into their motherboards running on the Intel 9 series chipsets.
WD's Senior Director of Platform Engineering Kevin Peterson has showcased the world's first-ever hard drive with PCIe support at Computex 2014.
According to Kevin Peterson, in the future, the speed of global data creation is likely to dramatically increase, especially with IoT applications becoming more widespread, which will likely result in a steep growth. This will come as a strong contrast to the relatively flat growth of storage devices. This demand gap between the two sectors will create endless opportunities for hardware equipment vendors. However, whether or not they will be able to seize this business opportunity will depend on whether or not there is a high-speed interface available for speeding up data processing rates. It is clear that the SATA 6G specifications alone cannot meet user expectations.
With SATA Express, vendors can use a new type of connector to simultaneously route both PCIe and SATA interface signals, thereby integrating the world's most popular computer bus with the world's most popular storage bus. This innovative combination allows users to use a single bus for SSDs, SSHDs, or HDDs. It also allows SATA's transmission speed to exceed the 550MB/s limit, further advancing toward the second-generation PCIe x2 interface's 900MB/s, or even the third-generation PCIe x2 interface's 1,800MB/s. Many of the storage applications that have been available in recent years have been developed around standard SATA technology, which is why SATA Express is an extremely meaningful development for users. SATA Express has the ability to provide a path for significant improvements to the existing applications environment.
SATA Express features the SRIS (Separate RefClock with Independent SSC) technology that allows the removal of the PCIe Sync line. This means that PCIe components that support SRIS will automatically produce their own clock signals, without the main system and device having to jointly send reference clock signals, thereby achieving the benefits of SSC. This way, computer manufacturers can maintain synchronization between the main system and devices simply by using a general PCIe connection, thereby reducing overall connection costs.
Kevin Peterson stressed that WD is at the forefront of SATA-based technologies, and clearly sees a future market where SATA Express will be the mainstream. This is why it is showcasing its SATA Express prototype at Computex 2014. This brand-new platform is built around a SATA Express core architecture in a dual hard drive environment consisting of a 128GB SSD and 4TB HDD. It also uses a standard AHCI driver, providing compatibility with existing user-end operating systems.
Extensive tests have shown that the read/write speeds provided by this architecture are consistently maintained at 680-700MB/s, clearly exceeding the performance of traditional SATA technologies.
However, there is clearly still room for taking the performance beyond 700MB/s to approach the 900MB/s limit of the second-generation PCIe x2 interface. Therefore, WD hopes that motherboard manufacturers will continue to work on it to boost performance to almost 900MB/s by using SSDs and HDDs with even better specifications, as well as optimizing the designs of their architectures. Furthermore, WD is looking to extend its partnerships from the PC motherboard sector to the server or even testing equipment sector, creating a diverse environment for the development of ubiquitous end-to-end high-speed storage applications.
Kevin Peterson, Senior Director of Platform Engineering at WD