Spark vs MapReduce: Who is Winning?

Big data is everywhere. Wait till 2021 and you will have over 50 billion Internet-connected devices, thanks to Internet of Things (IoT). All this relates to one thing—data is on a scale that is unprecedented in the history of humankind. For instance, 90 percent of the data that is in existence today was created in the last two years alone.

All this means that there needs to be a radical new way to handle all that data, process it in hitherto unheard volumes, and derive meaningful insights from it to help businesses leap forward in this cut-throat corporate scenario. This is where the argument comes into the picture: whether Apache MapReduce has run its course and is being taken over by a nimbler rival technology, Apache Spark.

Some of the interesting facts about these two technologies are as follows:

• Spark Machine Learning abilities are obtained by MLlib.
• Apache Spark can be embedded in any OS.
• Execution of a Map task is followed by a Reduce task to produce the final output.
• Output from the Map task is written to a local disk, while the output from the Reduce task is written to HDFS.

Check out the video on Spark vs MapReduce to learn more:

Spark Vs. MapReduce

Check out the detailed comparison between these two technologies.

What Are MapReduce and Spark?

The above table clearly points out that Apache Spark is way better than Hadoop MapReduce or, in other words, more suitable for the real-time analytics. However, it would be interesting to know what makes Spark better than MapReduce. But, before that you should know what exactly these technologies are. Read below:

MapReduce is a methodology for processing huge amounts of data in a parallel and distributed setting. Two tasks undertaken in the MapReduce programming are the Mapper and the Reducer. Mapper takes up the job of sorting data that is available, and Reducer is entrusted with the task of combining the data and converting it into smaller chunks. MapReduce, HDFS, and YARN are the three important components of Hadoop systems.

Spark is a new and rapidly growing open-source technology that works well on cluster of computer nodes. Speed is one of the hallmarks of Apache Spark. Developers working in this environment get an application programming interface that is based on the framework of RDD (Resilient Distributed Dataset). RDD is nothing but the abstraction provided by Spark that lets you segregate nodes into smaller divisions on the cluster in order to independently process data.

What Makes MapReduce Lag Behind in the Race?

So far, you must have perceived a clear picture of Spark and MapReduce workflows. It is clear that MapReduce is not suitable according to the evolving real-time big data needs. The following are the reasons behind this fact:

• Response time today has to be super fast.
• There are scenarios when the data from the graph has to be extracted.
• Sometimes, mapping generates a lot of keys which take time to sort.
• There are times when diverse sets of data need to be combined.
• When there is Machine Learning involved, then this technology fails.
• For repeated processing of data, it takes too much for the iterations.
• For tasks that have to be cascaded, there are a lot of inefficiencies involved.

How Does Spark Have an Edge over MapReduce?

Some of the benefits of Apache Spark over Hadoop MapReduce are given below:

• Processing at high speeds: The process of Spark execution can be up to 100 times faster due to its inherent ability to exploit the memory rather than using disk storage. MapReduce has a big drawback since it has to operate with the entire set of data in the Hadoop Distributed File System on the completion of each task, which increases the time and cost of processing data.
• Powerful caching: When dealing with Big Data, there is a lot of caching involved and this increases the workload while using MapReduce, but Spark does it in memory.
• Increased iteration cycles: There is a need to work on the same data again and again, especially in Machine Learning scenarios, and Spark is perfectly suitable for such applications.
• Multiple operations using in-built libraries: MapReduce is capable of using in-built libraries for batch processing tasks. Whereas, Spark provides the option of utilizing the in-built libraries to build interactive queries in SQL, Machine Learning, streaming, and batch processing, among other things.

Some Other Obvious Benefits of Spark over MapReduce

Spark is not tied to Hadoop, unlike MapReduce which cannot work outside of Hadoop. So, there are talks going around with subject matter experts claiming that Spark might one day even phase out Hadoop, but there is still a long way ahead. Spark lets you write an application in a language of your choice like Java, Python, and so on. It supports streaming data and SQL queries and extensive use of data analytics in order to make sense of the data, and it might even support machine-led learning like the IBM Watson cognitive computing technology.

Bottom Line

Spark is able to access diverse data sources and make sense of them all. This is especially important in a world where IoT is gaining a steady groundswell and machine-to-machine communications amount to a bulk of data. This also means that MapReduce is not up to the challenge to take on the Big Data exigencies of the future.

In the race to achieve the fastest way of doing things, using the least amount of resources, there will always be a clash of the Titans. The future belongs to those technologies that are nimble, adaptable, resourceful, and most of all can cater to the diverse needs of enterprises without a hitch, and Apache Spark seems to be ticking all the checkboxes, and possibly the future belongs to it.