lockable memory

Memory that can be locked (that is, its pages kept in real memory for the lifetime of a process)

 

by the kernel, by mlock(), or by plock() is known as lockable memory. Locked memory

 

cannot be paged or swapped out.

Logical Volume

A disk-management tool used to partition physical disk drives.

Manager (LVM)

 

memory cap

An upper limit on a PRM group’s memory use.

memory isolation

A way of separating a PRM group’s memory so that it cannot loan out to, or borrow memory

 

from, other groups.

memory manager

A daemon that monitors use of real memory on the system to ensure that PRM groups are granted

 

their memory allocations of private memory and shared memory. This daemon also enforces

 

capping of private memory when requested.

memory record

Record in a PRM configuration file that specifies a group’s memory allocation, either of private

 

memory or shared memory.

MRG

Memory Resource Group.

NFS

Network File System.

OTHERS group

The PRM group OTHERS with PRMID 1. PRM uses this group as the initial group for any user who

 

does not have a PRM user record in the PRM configuration file.

parent group

Any PRM group in a hierarchy that has child groups.

PID

Process ID.

polling interval

Amount of time a resource manager waits between its pollings of the system to determine

 

application placement or resource use. The polling interval is only used by the application manager

 

(APPL) and the memory manager (MEM).

POSIX real-time

A process that uses the POSIX.4 real-time scheduler (rtsched). This type of process keeps its

process

assigned priorities because timely scheduling is crucial to the operation of a real-time process.

 

Hence, such a process is permitted to exceed its CPU shares.

PRM administrator

A person responsible for PRM configuration. This person has root user capabilities.

PRM group

Collection of users and applications that are joined together and assigned certain amounts of

 

CPU and memory resources. Each group has a name and PRMID. These groups are defined in

 

a PRM configuration file. A PRM group record may define a traditional PRM group (FSS PRM

 

group) or a PSET PRM group.

PRM group ID

PRMID.

PRM_SYS group

The PRM group PRM_SYS with PRMID 0. PRM places all system processes in this group by default.

 

System processes are processes started by someone with UID 0.

PRMID

A value that may be used in place of the PRM group name. For FSS PRM groups, it is an integer

 

between 0 and 63 (inclusive) or between 0 and 255 (inclusive) starting with HP-UX 11i v2 Update

 

2. PRMIDs for PSET PRM groups are assigned by PRM. PRMID 0 (PRM_SYS) is reserved for the

 

system group. PRMID 1 (OTHERS) is reserved for the user default group.

process group ID

Each process group is uniquely identified by an integer called a process group ID. Each process

 

group also has a process group leader. The process group’s ID is the same as the process ID of

 

the process group leader. Every process in a process group has the same group ID.

process group

Every process (except system processes, such as init and swapper) belongs to a process

 

group. (Process groups are different from PRM groups.) A newly created process joins the process

 

group of its creator. When you create a job, the shell assigns all the processes in the job to the

 

same process group. Signals can propagate to all processes in a process group; this is a principal

 

advantage of job control.

process ID

An integer, assigned to a process at creation, that uniquely identifies the process to HP-UX.

processor set

A subset of the system’s cores. The default processor set consists of all cores on the system.

proportional

The ratio of memory used to memory entitlement for a group, compared to the average of all

overachievement

groups. If a PRM group is overachieving compared to the average, then the number of import

 

pages for that group is reduced, allowing other groups to start importing the newly available

 

memory.

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HP Process Resource Manager (PRM) manual Others group