Application Clustering

Onload User Guide (UG1586)

Document ID
Release Date
1.2 English

For details of Application Clustering, refer to Application Clustering.

  • Onload matches the Linux kernel implementation such that clustering is not supported for multicast traffic and where setting of SO_REUSEPORT has the same effect as SO_REUSEADDR.
  • Calling connect() on a TCP socket which was previously subject to a bind() call is not currently supported. This will be supported in a future release.
  • An application cluster will not persist over adapter/server/driver reset. Before restarting the server or resetting the adapter the Onload applications should be terminated.
  • The environment variable EF_CLUSTER_RESTART determines the behavior of the cluster when the application process is restarted - refer to EF_CLUSTER_RESTART in Parameter Reference.
  • If the number of sockets in a cluster is less than EF_CLUSTER_SIZE, a portion of the received traffic will be lost.
  • There is little benefit when clustering involves a TCP loopback listening socket as connections will not be distributed amongst all threads. A non-loopback listening socket - which might occasionally get some loopback connections can benefit from Application Clustering.