Socket Direct Protocol

RDMA (Remote Direct Memory Access) enables moving data directly from the memory of one computer to another computer, bypassing the operating system of both computers and resulting in significant performance gains.

The Sockets Direct Protocol (SDP) is a networking protocol developed to support stream connections over InfiniBand fabric. SDP support was introduced to the JDK 7 release of the Java Platform, Standard Edition ("Java SE Platform") for applications deployed in the Solaris Operating System ("Solaris OS") and on Linux operating systems.

There are no API changes required in your code to take advantage of the SDP protocol: the implementation is transparent and is supported by the classic networking (java.net) and the New I/O (java.nio.channels) packages.

SDP support is disabled by default. The steps to enable SDP support are:

1. Create an SDP configuration file.

2. Set the system property that specifies the location of the configuration file. (java -Dcom.sun.sdp.conf=sdp.conf -Djava.net.preferIPv4Stack=true ExampleApplication)

References:

• 1. Java SE tutorial - <Understanding the Sockets Direct Protocol>

  2. http://www.infoq.com/cn/articles/Java-7-Sockets-Direct-Protocol