HP Virtual Server Environment: Tips for Application Developers

Host via one of the methods described below, e.g., iCAP activations or deactivations. Increasing the
total number of cores will automatically benefit the virtual machines running on the physical system
because the virtual CPUs will appear to run "faster" because they have more physical core cycles
allocated to them over time.
Optimizing storage and I/O in a virtual machine requires special consideration. Because an Integrity
VM uses virtual hardware, high availability (HA) solutions such as multi-pathing and RAID (that
address physical hardware failure) do not apply. The result is, in most cases, even more flexible than
on a physical server. For example, multi-pathing configuration and management may be done on the
Integrity VM Host, and the storage accessed by that multi-pathing technology is then used as virtual
storage by the virtual machines. In this scenario, the virtual machines are effectively applications that
benefit from the Integrity VM Host system's multi-pathing configuration. If an I/O hardware failure
occurs, the multi-path technology automatically switches the I/O over to the alternate path and the
application - in this case a virtual machine - automatically benefits. This same paradigm applies to
other means of HA for I/O, including RAID and auto port aggregation.
Other, more general HA solutions may not yet be supported in virtual environment. Serviceguard is
currently the only major HA solution for applications running on Integrity VM.
Deploying Applications with Workload Managers
HP-UX Workload Manager (WLM) and HP Global Workload Manager (gWLM) are powerful
components of VSE that automate the allocation of resources among the applications which are
sharing the server infrastructure. The WLM and gWLM products automatically migrate processors, or
redistribute processor shares, across partitions based on defined service-level agreements that the
administrator establishes. In addition, they can activate and deactivate reserve capacity using
Temporary Instant Capacity for example. Normally the workload managers automate and optimize
operations that could be performed manually by an operator, but they can do it much more
accurately and efficiently.
Applications work with HP’s workload managers transparently. No changes to the applications are
needed to support execution under workload manager control.
It is possible to deploy a “workload management toolkit” if performance information from the
application is to be integrated into HP-UX WLM. In general, this is not necessary. For additional
information about HP-UX WLM Toolkit consult the HP-UX Workload Manager webpage at
http://www.hp.com/go/wlm.
Conclusion
The HP Virtual Server Environment is a powerful solution for achieving virtualization; it provides the
ability to pool and share server resources so that demand meets supply dynamically and
automatically. HP VSE has been designed to support third-party applications transparently. Some
applications can use additional information about the dynamic state of resources in an HP VSE to
deliver a higher level of performance and flexibility. For those applications, a robust set of interfaces
are available.
References
1. HP Virtual Server Environment
( http://hp.com/go/vse)
2. HP’s Developer and Solution Partner Program