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A lot of big data is created by using automated processes and instrumentation nowadays, and because data storage costs are relatively inexpensive, system velocity is, many times, the limiting factor. Keep in mind that big data is low-value. Consequently, you need systems that are able to ingest a lot of it, on short order, to generate timely and valuable insights.

In engineering terms, data velocity is data volume per unit time. Big data enters an average system at velocities ranging between 30 kilobytes (K) per second to as much as 30 gigabytes (GB) per second. Latency is a characteristic of all data systems, and it quantifies the system’s delay in moving data after it has been instructed to do so. Many data-engineered systems are required to have latency less than 100 milliseconds, measured from the time the data is created to the time the system responds.

Throughput is a characteristic that describes a systems capacity for work per unit time. Throughput requirements can easily be as high as 1,000 messages per second in big data systems! High-velocity, real-time moving data presents an obstacle to timely decision-making. The capabilities of data-handling and data-processing technologies often limit data velocities.

Tools that intake data into a system — otherwise known as data ingestion tools — come in a variety of flavors. Some of the more popular ones are described in the following list:

 Apache Sqoop: You can use this data transference tool to quickly transfer data back-and-forth between a relational data system and the Hadoop distributed file system (HDFS) — it uses clusters of commodity servers to store big data. HDFS makes big data handling and storage financially feasible by distributing storage tasks across clusters of inexpensive commodity servers.

 Apache Kafka: This distributed messaging system acts as a message broker whereby messages can quickly be pushed onto, and pulled from, HDFS. You can use Kafka to consolidate and facilitate the data calls and pushes that consumers make to and from the HDFS.

 Apache Flume: This distributed system primarily handles log and event data. You can use it to transfer massive quantities of unstructured data to and from the HDFS.