Accelerating Spark RDD Operations with Local and Remote GPU Devices

Abstract

Apache Spark is a distributed processing framework for large-scale data sets, where intermediate data sets are represented as RDDs (Resilient Distributed Datasets) and stored in memory distributed over machines. To accelerate its various computation intensive operations, such as reduction and sort, we focus on GPU devices. We modified Spark framework to invoke CUDA kernels when computation intensive operations are called. RDDs are transformed into array structures and transferred to GPU devices when necessary. Although we need to cache RDDs in GPU device memory as much as possible in order to hide the data transfer overhead, the number of local GPU devices mounted in a host machine is limited. In this paper, we propose to use remote GPU devices which are connected to a host machine via a PCI-Express over 10Gbps Ethernet technology. To mitigate the data transfer overhead for remote GPU devices, we propose three RDD caching policies for local and remote GPU devices. We implemented various reduction programs (e.g., Sum, Max, LineCount) and transformation programs (e.g., SortByKey, PatternMatch, WordConversion) using local and remote GPU devices for Spark. Evaluation results show that Spark with GPU outperforms the original software by up to 21.4x. We also evaluate the RDD caching policies for local and remote GPU devices and show that a caching policy that minimizes the data transfer amount for remote GPU devices achieves the best performance.