Recently at storm-users

I’ve been reading through storm-users Google Group recently. This
resolution was heavily inspired by Adam Kawa’s post “Football zero, Apache Pig hero”. Since I’ve encountered a lot of insightful and very interesting information I’ve decided to describe some of those in this post.

  • nimbus will work in HA mode – There’s a pull request open for it already… but some
    recent work (distributing topology files via Bittorrent) will greatly
    simplify the implementation. Once the Bittorrent work is done we’ll look
    at reworking the HA pull request. (storm’s pull request)

  • pig on storm – Pig on Trident would be a cool and welcome project. Join
    and groupBy have very clear semantics there, as those concepts exist
    directly in Trident. The extensions needed to Pig are the concept of
    incremental, persistent state across batches (mirroring those concepts
    in Trident). You can read a complete proposal.

  • implementing topologies in pure python with petrel looks like this:

class Bolt(storm.BasicBolt):
    def initialize(self, conf, context):
       ''' This method executed only once '''
        storm.log('initializing bolt')

    def process(self, tup):
       ''' This method executed every time a new tuple arrived '''       
       msg = tup.values[0]
       storm.log('Got tuple %s' %msg)

if __name__ == "__main__":
  • Fliptop is happy with storm – see their presentation here

  • topology metrics in 0.9.0: The new metrics feature allows you to collect
    arbitrarily custom metrics over fixed windows. Those metrics are
    exported to a metrics stream that you can consume by implementing
    IMetricsConsumer and configure with
    Use TopologyContext#registerMetric to register new metrics.

  • storm vs flume – some users’ point of view: I use Storm and Flume and find that they are better at
    different things – it really depends on your use case as to which one is
    better suited. First and foremost, they were originally designed to do
    different things: Flume is a reliable service for collecting,
    aggregating, and moving large amounts of data from source to destination
    (e.g. log data from many web servers to HDFS). Storm is more for
    real-time computation (e.g. streaming analytics) where you analyse data
    in flight and don’t necessarily land it anywhere. Having said that,
    Storm is also fault-tolerant and can write to external data stores (e.g.
    HBase) and you can do real-time computation in Flume (using

That’s all for this day – however, I’ll keep on reading through storm-users, so watch this space for more info on storm development.