In HHH-M mode, we evaluate the performance of RDMA-enhanced HDFS with in-memory I/O operations by TestDFSIO benchmark. For detailed configuration and setup, please refer to our userguide.

TestDFSIO Latency and Throughput

TestDFSIO Latency

dfsio ri2 time

TestDFSIO Throughput

dfsio ri2 thruput

Experimental Testbed: Each node in OSU-RI2 has two fourteen Core Xeon E5-2680v4 processors at 2.4 GHz and 512 GB main memory. The nodes support 16x PCI Express Gen3 interfaces and are equipped with Mellanox ConnectX-4 EDR HCAs with PCI Express Gen3 interfaces. The operating system used is CentOS 7.

These experiments are performed in 8 DataNodes with a total of 64 maps. Each DataNode has a single 2TB HDD, single 400GB PCIe SSD, and 252GB of RAM disk. HDFS block size is kept to 128 MB. Each NodeManager is configured to run with 12 concurrent containers assigning a minimum of 1.5GB memory per container. The NameNode runs in a different node of the Hadoop cluster. 70% of the RAM disk is used for HHH data storage.

The RDMA-IB design improves the job execution time of TestDFSIO by a maximum of 3.7x over IPoIB (100Gbps). It provides a maximum of 3.3x benefit in throughput experiment, compared to IPoIB (100Gbps).

TestDFSIO Latency and Throughput

TestDFSIO Latency

dfsio comet time

TestDFSIO Throughput

dfsio comet thruput

Experimental Testbed: Each compute node in this cluster has two twelve-core Intel Xeon E5-2680v3 processors, 128GB DDR4 DRAM, and 320GB of local SSD with CentOS operating system. Each node has 64GB of RAM disk capacity. The network topology in this cluster is 56Gbps FDR InfiniBand with rack-level full bisection bandwidth and 4:1 oversubscription cross-rack bandwidth.

The TestDFSIO experiments are performed in 16 DataNodes with a total of 128 maps. HDFS block size is kept to 128 MB. The NameNode runs in a different node of the Hadoop cluster and the benchmark is run in the NameNode. The RDMA-IB design improves the job execution time of TestDFSIO by a maximum of 1.7x over IPoIB (56Gbps). The improvement in throughput is up to 1.8x.