PRM : Process resource Manager in HP unix

Process Resource Manager (PRM) is a resource management tool used to control the amount of resources that processes use during peak system load
(at 100% CPU resource or 100% memory resource). PRM can guarantee a minimum allocation of system resources available to a group of
processes through the use of PRM groups.

A PRM group is a collection of users and applications that are joined together and assigned certain amounts of CPU and memory resource.
The two types of PRM groups

1.FSS PRM groups
2.PSET PRM groups

FSS PRM groups :

FSS PRM group is the traditional PRM group. whose CPU entitlement is specified in shares. This group uses the Fair Share Scheduler (FSS) in the HP-UX kernel within the system’s default processor set (PSET).

PSET PRM groups :

A PSET PRM group is a PRM group whose CPU entitlement is specified by assigning it a subset of the system’s cores (PSET).
(A core is the actual data-processing engine within a processor. A single processor might have multiple cores.  A core might support multiple execution threads.)
Processes in a PSET have equal access to CPU cycles on their assigned cores through the HP-UX standard scheduler.

Commands in PRM :

#Configure PRM, initiate /etc/prmconf configuration file
prmconifg -i

#Check the configuration file settings
prmconfig -s

#Enable PRM
prmconfig -e

#Disable PRM
prmconfig -d

#Monitor PRM
prmmonitor

#List available PRM resource
prmavail



Configuration Steps:

1. Gather the basic resource information by prmavail
2. Initiate /etc/prmconf and start editing
3. Define the FSS group
4. Define the Resource type and limit
5. Run prmconfig -i -e to enable PRM
6. Enable auto start up in /etc/rc.config.d/prm

   PRM_CONFIG=1
   PRM_ENABLE=1