Pathway/XM System Management Manual

Configuring the Pathway/XM Environment

Compaq NonStop™ Pathway/XM System Management Manual—426761-001

4-16

Specifying the System (Physical Node)

The SYSTEM attribute specifies the name of the NonStop™ Himalaya system to which

the NODE object applies. All processes to which this NODE object applies will be

started in the specified CPUs (given in the CPUS attribute) on the specified Compaq

system.

If this attribute is not defined, PXMCFG uses the name of the system on which it is

running. It is recommended that you use this attribute to specify the system name

explicitly.

Specifying the Volume for Pathway/XM Object Files

To find the Pathway/XM object-code files to be used when starting PATHMON,

PATHCOM, process broker (PB), and link control service (LCS) processes, PXMCOM

looks on the disk volume specified in the GUARDIAN-SWAP attribute for the

applicable client NODE object. You must set this attribute to the name of the volume

on which these product files were installed by the Install program or the DSM/SCM

utility. (For software releases that do not use the Kernel Managed Swap Facility

(KMSF) to manage swap space, the GUARDIAN-SWAP attribute also identifies the

location of swap files.)

The GUARDIAN-SWAP attribute is not used to find the object-code file for TCPs.

When starting a TCP, PXMCOM uses the volume, subvolume, and file ID specified in

the PROGRAM attribute of the TCP template.

Specifying CPUs and CPU Weights

The CPUS attribute specifies a set of processors (CPUs) to be used for running

processes and the distribution percentage (weight) of those processes that should be run

in each specified CPU. PXMCFG uses these CPU and weight specifications to assign

processes to processors in the initial configuration.

PXMCOM and the PB processes use the CPU and weight specifications to keep the

process workload balanced as they create new processes. Processes are created only

when the configuration or the transaction workload requires them. Both PXMCFG and

the PBs assign processes to CPUs in a round-robin fashion according to the specified

weights.

You must specify at least two CPUs for each NODE object, so that Pathway/XM can

assign CPUs for primary and backup processes. The total of the weight values for all

CPUs specified for a NODE object must be equal to 100. If you do not specify weight

values, Pathway/XM divides the weight of 100 evenly among all specified CPUs.

For example, the following SET statement specifies five processors for a NODE object:

SET NODE CPUS (1:22, 3:31, 5:31, 6:8, 9:8)

This NODE object defines the use of processors 1, 3, 5, 6, and 9 with relative weights of

22, 31, 31, 8, and 8 percent, respectively. This means that the first process started under

this NODE object will be in CPU 1; when a number of processes have been started, the

greatest number of processes will be assigned to CPUs 3 and 5; and that CPUs 6 and 9