OpenVMS Cluster Systems - OpenVMS Systems - HP

Table A–1 (Cont.) Adjustable Cluster System Parameters
Parameter Description
‡MC_SERVICES_P0
(dynamic)
Cluster System Parameters
A.1 Values for Alpha and VAX Computers
Controls whether other MEMORY CHANNEL nodes in the cluster continue
to run if this node bugchecks or shuts down.
A value of 1 causes other nodes in the MEMORY CHANNEL cluster to fail
with bugcheck code MC_FORCED_CRASH if this node bugchecks or shuts
down.
The default value is 0. A setting of 1 is intended only for debugging
purposes; the parameter should otherwise be left at its default state.
‡MC_SERVICES_P2 (static) Specifies whether to load the PMDRIVER (PMA0) MEMORY CHANNEL
cluster port driver. PMDRIVER is a new driver that serves as the MEMORY
CHANNEL cluster port driver. It works together with MCDRIVER (the
MEMORY CHANNEL device driver and device interface) to provide
MEMORY CHANNEL clustering. If PMDRIVER is not loaded, cluster
connections will not be made over the MEMORY CHANNEL interconnect.
The default for MC_SERVICES_P2 is 1. This default value causes
PMDRIVER to be loaded when you boot the system.
Compaq recommends that this value not be changed. This parameter value
must be the same on all nodes connected by MEMORY CHANNEL.
‡MC_SERVICES_P3
(dynamic)
Specifies the maximum number of tags supported. The maximum value is
2048 and the minimum value is 100.
The default value is 800. Compaq recommends that this value not be
changed.
This parameter value must be the same on all nodes connected by MEMORY
CHANNEL.
‡MC_SERVICES_P4 (static) Specifies the maximum number of regions supported. The maximum value
is 4096 and the minimum value is 100.
The default value is 200. Compaq recommends that this value not be
changed.
This parameter value must be the same on all nodes connected by MEMORY
CHANNEL.
‡MC_SERVICES_P6 (static) Specifies MEMORY CHANNEL message size, the body of an entry in a free
queue, or a work queue. The maximum value is 65536 and the minimum
value is 544. The default value is 992, which is suitable in all cases except
systems with highly constrained memory.
For such systems, you can reduce the memory consumption of MEMORY
CHANNEL by slightly reducing the default value of 992. This value must
always be equal to or greater than the result of the following calculation:
‡Alpha specific
1. Select the larger of SCS_MAXMSG and SCS_MAXDG.
2. Round that value to the next quadword.
This parameter value must be the same on all nodes connected by MEMORY
CHANNEL.
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Cluster System Parameters A–3