HyperFabric Configuration Guidelines

Hyper Messaging Protocol (HMP)

Configuring HMP Local Failover for Oracle

Each Oracle process (using HMP) allocates resources like NQs and EPTs

(memory and receive end point). Values of these parameters are read by

the HMP subsystem when the first process of an application registers

with HMP, and these values are used to statically size HMP’s internal

data structures.

CLIC_ATTR_APPL_MAX_PROCS --->The maximum number of

processes that each application (like Oracle) can register with HMP

subsystem.

CLIC_ATTR_APPL_MAX_NQS --->The maximum number of

notification queues that each application can create. For Oracle, this is

same as MAX_PROCS as each Oracle process creates 1 NQ while

registering with HMP.

For local failover to be supported, 2 NQs must be allocated for each NQ

allocation requested. So, CLIC_ATTR_APPL_MAX_NQS value must be

set to the 2 times (or greater) the value of

CLIC_ATTR_APPL_MAX_PROCS. However, it should be well within

4999.

So, for local failover with Oracle, CLIC_ATTR_APPL_MAX_PROCS

must be set to half the value of CLIC_ATTR_APPL_MAX_NQS.

CLIC_ATTR_APPL_MAX_MEM_EPTS,CLIC_ATTR_APPL_MAX_REC

V_EPTS-->this is the maximum number of memory and receive EPTs (

Sender managed) for a given application. Again, for local failover, 2 EPTs

must be allocated or each allocation request.

CLIC_ATTR_APPL_DEFLT_PROC_SENDS --> The maximum number

of send requests that can be queued up without the process collecting the

send completion event.

CLIC_ATTR_APPL_DEFLT_NQ_RECVS --> The maximum number of

receive notifications that can be queued up in a notification queue

without the receiver process collecting the receive notification to

ensuring that NQ is not overflowing.

Also, note that the maximum values for each of these parameters are on

a per HP-UX instance basis. The assumption is that Oracle is the only

application that uses HMP.