HP-UX HB v13.00 Ch-19 - PRM

HP-UX Handbook – Rev 13.00 Page 29 (of 31)
Chapter 19 Process Resource Manager (PRM)
October 29, 2013
CPU Hogger Source Code
The following C program is suited to test the functionality of PRM’s CPU
resource manager. It simply tries to consume as much CPU time as it can get.
# cat cpuhogger.c
main()
{
while (1);
}
NOTE: A process can only execute on one CPU at a time. Hence a single cpuhogger process can
never use 50% CPU time on an 8-way system. The maximum would be 12,5%. In order to
exploit the CPU time of a PRM group you may need to start more than one cpuhogger process.
Workload Manager (WLM)
HP-UX Workload Manager (WLM) supplements the functionality of HP Process Resource
Manager (PRM) by offering automatic resource allocation and dynamic application performance
management through prioritized service-level objectives (SLOs) - based on goal-based, time-
based, condition-based or usage-based criteria.
You can use WLM to manage system resources within resource partitions, in which case WLM
creates and manages its own PRM configuration (PRM must be installed on the same system).
You can use WLM to manage CPU resources across hard partitions and virtual partitions. WLM
automatically moves cores between partitions based on the SLOs in the partitions. (Given the
physical nature of hard partitions, the “movement” of cores among partitions is achieved by
deactivating a core on one nPartition and then activating a core on another.) You can use WLM
to manage resources within a virtual machine. On an Integrity Virtual Machines (Integrity VM)
host, you can use WLM to manage resources across partitions; within an Integrity VM guest, you
can use WLM to manage the HP-UX resources but not using Instant Capacity (iCAP, formerly
known as HP Instant Capacity on Demand, or iCOD), Pay per use (PPU), or virtual partition
integration.
Resource partitions - Resource partitions are provided by HP Process Resource Manager (PRM)
to manage processor sets and Fair Share Scheduler (FSS) groups. These partitions enable you to
partition system resources (including memory and disk bandwidth) within a single instance of
HP-UX and consolidate multiple workloads within that instance. You can use these partitions
within (but not across) hard partitions and virtual partitions.