Showing posts with label event-driven. Show all posts
Showing posts with label event-driven. Show all posts

13 May 2017

Vs Of Big Data

Volume - amount of data
Velocity - speed of data flowing into a system
Variety - different types of data from multiple sources
Veracity - accuracy of inbound and outbound data

Many tools exist that address the above characteristics of Big Data which can be split into three different purposeful strands:
  • Data Transfer - e.g Kafka, Flume, Scribe, Scoop
  • Data Storage - e.g Hadoop, GlusterFS, Cassandra
  • Data Processing - e.g Storm, Flink, Spark, Samza

4 May 2017

Delivery Patterns

  • At-Most-Once : Messages may be lost, least desirable
  • At-Least-Once : Messages may be redelivered - no loss but may include duplicates
  • Exactly-Once : Messages are delivered once and only once - no loss and no duplicates, but difficult to guarantee

In order to manage state, messages may be stored in an embedded key-value store, a distributed file system, or use a higher level of abstraction.