1.4 Technology Preview

The following features included in the Unbreakable Enterprise Kernel Release 3 are still under development, but are made available for testing and evaluation purposes.

  • DRBD (Distributed Replicated Block Device)

    A shared-nothing, synchronously replicated block device (RAID1 over network), designed to serve as a building block for high availability (HA) clusters. It requires a cluster manager (for example, pacemaker) for automatic failover.

  • Kernel module signing facility

    Applies cryptographic signature checking to modules on module load, checking the signature against a ring of public keys compiled into the kernel. GPG is used to do the cryptographic work and determines the format of the signature and key data.

  • Transcendent memory

    Transcendent Memory (tmem) provides a new approach for improving the utilization of physical memory in a virtualized environment by claiming underutilized memory in a system and making it available where it is most needed. From the perspective of an operating system, tmem is fast pseudo-RAM of indeterminate and varying size that is useful primarily when real RAM is in short supply. To learn more about this technology and its use cases, see the Transcendent Memory project page at https://oss.oracle.com/projects/tmem/.

  • NFS over RDMA Client

    Enables you to use NFS over the RDMA transport on the Oracle InfiniBand stack. This is more efficient than using the TCP/IPoIB transport. The technology preview does not include NFS over RDMA server support, or support for NFS over RDMA in virtualized environments. NFS version 3 and 4 are supported. Currently, only the Mellanox ConnectX-2 and ConnectX-3 Host Channel Adapters (HCAs) are supported. The client passes the full Connectathon NFS test suite using these HCAs. The Release Notes will be updated if additional adapters are supported after the initial release.

    See Section 1.4.1, “Using the NFS over RDMA Client” for details of how to use the feature.