Baidu – The SSD Guy Blog

The Storage Developer Conference in September gave a rare glimpse into two very different directions that SSD architectures are pursuing. While some of the conference’s presentations touted SSDs with increasing processing power (Eideticom, NGD, Samsung, and ScaleFlux) other presentations advocated moving processing power out of the SSD and into the host server (Alibaba, CNEX, and Western Digital).

Why would either of these make sense?

A standard SSD has a very high internal bandwidth that encounters a bottleneck as data is forced through a narrower interface. It’s easy to see that an SSD with 20+ NAND chips, each with an 8-bit interface, could access all 160 bits simultaneously. Since there’s already a processor inside the SSD, why not open it to external programming so that it can perform certain tasks within the SSD itself and harness all of that bandwidth?

Example tasks would include Continue reading “SSDs Need Controllers with More, NO! Less Power”

I have to admit that it’s embarrassing when The SSD Guy misses something important in the world of flash storage, but I only recently learned of a paper that Baidu, China’s leading search engine, presented at the ASPLOS conference a year ago. The paper details how Baidu changed the way they use flash to gain significant benefits over their original SSD-based systems.

After having deployed 300,000 standard SSDs over the preceding seven years, Baidu engineers looked for ways to achieve higher performance and more efficient use of the flash they were buying. Their approach was to strip the SSD of all functions that could be better performed by the host server, and to reconfigure the application software and operating system to make the best of flash’s idiosyncrasies.

You can only do this if you have control of both the system hardware and software.

The result was SDF, or “Software-Defined Flash”, a card that Continue reading “Baidu Goes Beyond SSDs”