AIX 5L Performance Tools Handbook
Abstract This IBM Redbook discusses the latest AIX 5L performance and tuning tools. It explains the use of each tool and how it takes the measurements and statistics it produces. It contains a large number of usage and output examples, pointing out the relevant statistics to look for when analyzing an AIX system's performance. It also explains the performance APIs that are available with AIX 5L and gives examples on how to create your own performance tools. An overview is provided of the graphical AIX performance tools available with AIX 5L and the AIX Performance Toolbox Version 3.0. For related information about this topic, refer to the following IBM Redbooks publication: AIX 5L Practical Performance Tools and Tuning Guide, SG24-6478-00
Contents AIX performance in a Partition Load Manager (PLM) environment
The Partition Load Manager (PLM) software is part of the Advanced POWER Virtualization feature. It helps customers to maximize the utilization of processor and memory resources of DLPAR-capable logical partitions running AIX 5L on pSeries servers. The PLM is a resource manager (works with RMC, part of RSCT), which assigns and moves resources based on defined policies and utilization of the resources in an IBM eServer pSeries based on POWER5 architecture (p5). PLM is able to manage memory, dedicated processor partitions, and shared processor partitions, using micro-partitioning technology to readjust the resources. This adds additional flexibility to the micro-partition flexibility offered by the POWER Hypervisor. PLM, however, has no knowledge of the importance of any workload running in the partitions and therefore cannot readjust priority based on the changes of workload types. PLM is set up in a partition or on another system running AIX 5L V5.2 ML4 or AIX 5L V5.3. To configure PLM, you can use the command line interface, or the Web-based System Manager for graphical setup. PLM uses a client/server model to report and manage resource utilization. The clients (managed partitions) notify the PLM server when resources are either under- or over-utilized. Upon notification of one of these events, the PLM server makes resource allocation decisions based on a policy file defined by the system administrator. PLM uses the Resource Monitoring and Control (RMC) subsystem for network communication, which provides a robust and stable framework for monitoring and managing resources. For communication with the Hardware Management Console (HMC) to gather system information and execute commands, PLM requires a configured SSH connection (both server and client running on all partitions managed by PLM).