HP-UX Processor Sets

HP-UX Processor Sets 25
Also, many applications are designed to scale to all available resources in the system with the
assumption that the entire system is available to them.
As servers with enough power to host many applications become available, the customers are
now looking to consolidate their applications into larger servers, although they still need
resource partitioning among applications to minimize interference and to guarantee necessary
resource allocation to each application. Processor sets provide an excellent lightweight and
flexible mechanism to partition a system’s processor resources among the applications
residing on the same server. For example, different departments in an organization who have
been running their own separate database servers, may now have their database servers
hosted on a larger HP-UX server. When used with HP-UX PRM, each instance of the
database servers can be assigned a subset of processors as well as memory in the system.
Processor Isolation for Real Time Applications
Real time applications expect somewhat deterministic responses or workload completion
times, and hence want zero-to-minimal interference from other running applications in the
system. In the past, there was no way to achieve this, so customers set up separate systems
for real-time applications. With processor sets, however, customers can now use a single
system to achieve the same objectives. Within the system, they can configure a processor set
with the required number of processors and bind only the real-time application to that
processor set.
Resource Partitioning among Users and Departments
Departments in an organization may be running their own email servers, as well as timeshare
servers for their users. Processor sets allow these servers to be consolidated into larger
systems.
Different departments may also have varying resource needs and budget constraints. With
processor sets, processor resources can be assigned and managed among users of different
departments based on their budget allocations.
Job Processing in Batch Mode
When processing jobs in a batch mode, the jobs are scheduled one after another, and
essentially no resource allocation is made on a per-job basis. In contrast, the dynamic
configuration feature of processor sets allows the system user to configure a processor set for
a given job based on the processor resource requirements for the job. The user can then
execute the job in the processor set and, when the job is finished,destroy the set. In short,
processor sets provide for a more deterministic job completion, and allow concurrent
scheduling of multiple jobs based on resource requirements and system size.