In a world where real-time data streams are becoming much more common, and with the volume of that data continuing to increase, it makes sense that a framework would be developed to increase the ease at which that data can be processed. Yahoo! S4 isn’t the first such framework to be concieved, or even open sourced, but it is likely to massively increase awareness that such frameworks exist, what problems they may help solve and get developers thinking about how they could use the technology and potentially increase the likelihood of somebody moving S4-like capabilities into the cloud and offering it as as service.

The requirement for a “distributed stream computing platform” came about for Yahoo! in order to be able to process thousands of search queries per second, from potentially millions of users per day,  to facilitate the generation of highly personalized adverts for web search. A new framework was required because Yahoo! felt that MapReduce, which is commonly used to process large datasets in batch jobs, was “hard to apply to stream computational tasks”.

Yahoo! describe the S4 framework using a number of terms that have become common place in the world of cloud computing:

S4 is a general-purpose, distributed, scalable, partially fault-tolerant, pluggable platform that allows programmers to easily develop applications for processing continuous unbounded streams of data.

Yahoo! S4 is yet another powerful real-time component now available to the Programmable Web. It opens up a number of possibilities for developers to start building exciting data-centric applications, mashups or hosted services which could integrate with other components such as real-time APIsreal-time client push services and DaaS services.