IT Career Guides & Free Resources
Expert roadmaps, tutorials, salary guides and interview prep across Data Science, Generative AI, Python, Cloud & Analytics — written by GloryTecks trainers in Hyderabad.
All articles
Apache Spark Explained for Beginners
A beginner's guide to Apache Spark: what it is for, how the driver, executors and cluster manager fit together, jobs, stages and tasks, lazy transformations and actions demonstrated on three million New York taxi trips, partitions, installing PySpark, and the mistakes beginners make.
Spark vs Hadoop: What Changed and Why
What changed when Spark overtook Hadoop MapReduce: the three parts of Hadoop, the MapReduce model emulated step by step on three million taxi trips with its intermediate data written to disk, why in-memory processing and DAGs mattered, what Spark still borrows from Hadoop, and what that means today.
Spark Performance Interview Questions
Spark performance questions ask what you would change, and how you would know it helped. Five tuning levers are tested on 3.5 million real taxi trips with evidence that does not depend on the machine: pushed-down filters in the plan, task counts, partition sizes before and after salting, join types, and cache hits.
Apache Spark Interview Questions and Answers
Spark interviews test whether you can predict what Spark will do with your code. Seven core questions are answered here with evidence from a real Spark session over three million taxi trips: job counts, physical plans, partition numbers and row distributions, instead of definitions recited from memory.
Spark Performance Tuning: Shuffles, Joins and Caching
A practical guide to Spark performance: reading the physical plan, why 200 shuffle partitions became one under adaptive query execution, how Spark chooses broadcast or sort-merge joins and how hints change it, what skew looks like in real partition sizes, when caching pays, and a tuning checklist.
Partitioning and Bucketing in Spark Explained
“Partition” means three different things in Spark: in-memory partitions, directory partitions on disk, and buckets. What each one controls, which setting or method changes it, and how to choose partition and bucket columns without creating millions of small files.