Java Workloads in the Cloud and Java Sockets over RDMA (JSOR)

Java Workloads in the Cloud and implementation of Java Sockets over RDMA (JSOR) will improve the Ethernet communications between distributed applications. So, Java on Linux got a new communication library capable of supporting the best performance of the high-speed network adapters.

The new protocol is introduced by IBM as Javaâ„¢ Sockets over RDMA (JSOR) for Java 7 for Linux/AMD64 platforms. The basic is that, it is designed to improve the throughput and reduce latency for client-server applications that reside in the cloud computing environments equipped with a RDMA-compatible high speed network card.

Official release News can be found here :

Java Workloads in the Cloud : Understanding remote direct memory access (RDMA)

Remote direct memory access (RDMA) is a direct memory access from the memory of one computer into that of another without involving either one’s operating system. This permits high-throughput, low-latency networking, which is especially useful in massively parallel computer clusters.

JSOR is available only on Linux 32-bit Intel and AMD64/EM64T platform architectures. Each Java application host must have an InfiniBand Host Control Adapter (HCA) or RDMA-enabled network interface adapter. These adapters must be interconnected by a high performance InfiniBand capable switch. You must install OpenFabrics Enterprise Distribution (OFED) v1.5.3, which can be downloaded from the OpenFabrics Alliance website :

Java Workloads in the Cloud, RDMA, JSOR and the Result

In short, with JSOR, IBM seeks to fill that gap in Java (on Linux) that prevented access to the RDMA communication protocol (R-Socket), as was the case for projects in C/C++.

This reduces the latency times up to 10 microseconds now, the protocol RDMA (R-Socket) was only available for routine C/ C++, as there are special APIs (such as Message Passing Interface) that allow you to implement and quickly use. Access to these APIs from Java applications introduces additional complexity of programming, which can be avoided by taking advantage of the new library JSOR.
JSoR is in fact capable of intercepting calls to the Java socket and route them directly through the underlying infrastructure RDMA-compatible.

As we know, traditionally RDMA reduces network protocol overhead, leading to improvements in communication latency. Reductions in protocol overhead can increase a network’s ability to move data quickly, allowing applications to get the data they need faster, in turn leading to more scalable clusters. However, one must be aware of the tradeoff between this reduction in network protocol overhead and additional overhead that may be incurred on each node due to the need for pinning virtual memory pages.