User's Guide

Planning the Fabric
Hyper Messaging Protocol (HMP)
Chapter 2
30
Hyper Messaging Protocol (HMP)
Hyper Messaging protocol (HMP) is HP patented, high performance cluster interconnect
protocol. HMP provides reliable, high speed, low latency, low CPU overhead, datagram
service to applications running on HP-UX platforms.
HMP was jointly developed with Oracle Corp. The resulting feature set was tuned to
enhance the scalability of the Oracle Cache Fusion clustering technology. It is
implemented using Remote DMA (RDMA) paradigms.
HMP is integral to the HP-UX HyperFabric driver. It is a functionality that can be
enabled or disabled at HyperFabric initialization using clic_init or SMH. The HMP
functionality is used by the applications listed in the Application Availability section
below.
HMP significantly enhances the performance of parallel and technical computing
applications.
HMP firmware on HyperFabric adapter cards provides a “shortcut” that bypasses
several layers in the protocol stack, boosting link performance and lowering latency. By
avoiding interruptions and buffer copying in the protocol stack, communication task
processing is optimized.
Application Availability
Currently there are two families of applications that can use HMP over the HyperFabric
interface:
• Oracle 9i Database, Release 1 (9.0.1) and Release 2 (9.2.0.1.0).
HMP has been certified on Oracle 9i Database Release 1 with 11i v3.
HMP has been certified on Oracle 9i Database Release 2 with 11i v3.
• Technical Computing Applications
Features
• OnLine Addition and Replacement (OLAR)
The OLAR feature, which allows the replacement or addition of HyperFabric adapter
cards while the system (node) is running, is supported when applications use HMP
to communicate.