NOTE

Planning the Fabric

Hyper Messaging Protocol (HMP)

Hyper Messaging Protocol (HMP)

Hyper Messaging protocol (HMP) is Hewlett-Packard’s 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 SAM. 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.

Although HMP is supported on some HF1 hardware (see Figure 2-6 on page 43), it is optimized to run on HF2 hardware.

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 HP-UX 11.0 and 11i. HMP has been certified on Oracle 9i Database Release 2 with HP-UX 11.0 and 11i.

Although HMP and TCP/IP applications are able to run simultaneously on the same HyperFabric cluster, for practical purposes, a HyperFabric cluster must run HMP applications exclusively or TCP/IP applications exclusively.

Features

OnLine Addition and Replacement (OLAR): Not Supported

The OLAR feature, which allows the replacement or addition of HyperFabric adapter cards while the system (node) is running, is not supported when applications use HMP to communicate.

Event Monitoring Service (EMS): Supported

Chapter 2

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HP HyperFabric manual Hyper Messaging Protocol HMP, Application Availability