When VLSI meets DBMS: The Story behind the World’s First SQL Chip
August 21st, 2008Posted by Raj Cherabuddi
In April this year, Kickfire announced the first high-performance appliance for MySQL. As part of the announcement, the company released data warehouse benchmark results that broke prior records in terms of price/performance and performance in a non-clustered environment. While the creation of a new appliance built exclusively for MySQL along with the benchmark records was noteworthy, perhaps the bigger story lies in what we believe to be the beginning of a paradigm shift in the database world - one marked by the advent of the first SQL chip.
To give some context to this story I have included a graph below which depicts the evolution of VLSI (Very-Large-Scale Integration) semiconductor technology and its growing impact on a broadening range of industries.
Specifically, this diagram shows that as VLSI density (# transistors per sq millimeter) has increased over time per Moore’s Law, it has been possible to transition an increasing number of applications from a “software/CPU” model to a “custom chip” model. Starting with Digital Signal Processing in the 1970’s through to SQL Processing today, there has been a long history of industries that have witnessed this transition and seen a major upheaval in the status quo.
Take graphics processing as an example. Initially, the graphics market was led by companies such as Silicon Graphics with their high-end terminals built on a combination of proprietary software and general-purpose CPUs. This all changed with the arrival of the graphics chip. Designed by companies like ATI and Nvidia, the graphics chip delivered a much higher price/performance ratio, which opened up high-end graphics processing to a much broader audience (e.g. gamers) and transformed the industry. Silicon Graphics, now called SGI, is worth $73M today. Nvidia is worth 100 times more at $7.3B.
The question you might be asking yourself is why these particular applications? What is it about these applications that made them suitable for such a transition? In a word, Dataflow.
The common characteristic underlying these application domains is that they all deal with the need to process large volumes of data at high speed. Now, general-purpose CPUs are based on the von Neumann architecture which was conceived in the 1940’s at a time when data volumes were much much smaller than today. This architecture is an instruction-centric or control flow one that is good at processing large numbers of instructions quickly but not well suited to processing large data sets due to the so-called von Neumann bottleneck.
What the pioneers in each of the application domains we mentioned discovered is that a Dataflow architecture is much better suited to solving the problem of high-volume data processing because it eliminates the von Neumann bottleneck. In a dataflow architecture the data, as opposed to instructions, flows directly through the execution engine. There are no wasted clock cycles spent waiting for data to arrive into the registers as in the case of the von Neumann architecture. The difference is significant. As an example, a single SQL chip from Kickfire provides better performance than 10’s of CPU cores, as demonstrated in the data warehouse benchmark results we published.
In my next post I’ll discuss this topic a little more, explaining why the transition from general-purpose CPU to custom chip is only happening now in the database world and why we believe this will be an irreversible trend.

