Choose your real-time weapon: Storm or Spark? @ InfoWorld
this is for Velocity: steaming data
bigdata - Apache Spark vs. Apache Storm - Stack Overflow
Spark, Storm and Real Time Analytics @ InfoQ
"Twitter has replaced Storm with Heron which provides up to 14 times more throughput and up to 10 times less latency on a word count topology, and helped them reduce the needed hardware to a third.
Twitter used Storm to analyze large amounts of data in real time for years, and open sourced it back in 2011. The project was later incubated at Apache, becoming a top level project last fall. Having a quarterly release cycle, Storm has reached version 0.9.5 and is approaching the stable and desired version 1.0. But all this time, Twitter has been working on a replacement called Heron because Storm is no longer up to the task for their real-time processing needs.
Twitter’s new real-time requirements are: “billions of events per minute; have sub-second latency and predictable behavior at scale;"
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"Compatibility with Storm: Heron provides full backward compatibility with Storm,"
"overall 3x reduction in hardware"
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Removing the 140 character limit from Direct Messages - Announcements - Twitter Developers
History of Apache Storm and lessons learned - thoughts from the red planet - thoughts from the red planet (by Nathan Marz, creator of Storm)
Twitter Heron: Stream Processing at Scale | the morning paper