Spark Tuning
What is Spark Tuning?
Spark Tuning refers to the process of adjusting settings to optimize memory, cores, and instances utilized by the system, ensuring seamless performance and avoiding resource bottlenecks in Apache Spark.
Data Serialization is crucial for reducing memory usage and enhancing network performance. Spark supports two serialization libraries: Java Serialization and Kryo Serialization. By terminating long-running jobs, utilizing resources efficiently, ensuring accurate execution engines, and improving system performance time, one can achieve outstanding results in Spark performance.
Memory Tuning is another vital aspect of Spark Performance Tuning. When tuning memory usage, consider the memory usage of the entire dataset, garbage collection overhead, and object access costs.
Data Structure Tuning effectively reduces memory consumption. By avoiding Java features that create overhead, such as nested structures, you can use multiple small objects and pointers instead. Numeric IDs and enumerated objects can replace strings for keys.
Garbage Collection Tuning is necessary to prevent the significant "churn" associated with previously stored RDDs. Using data structures with fewer objects, like an array of Ints instead of a linked list, can significantly reduce the cost. Alternatively, using objects in serialized form allows for a single object per RDD partition.
Memory Management is essential for optimal performance. Spark primarily uses memory for storage and execution. Memory contention presents three challenges for Apache Spark: arbitrating memory between execution and storage, managing memory across concurrently running tasks, and handling memory across operators within the same task. Addressing memory contention by forcing members to spill can help avoid statically reserving memory in advance.