|
|
United States-English | |
|
|
 |
|
HP-UX Workload Manager User's Guide: Version A.03.02.02 > Chapter 1 Introduction
What is HP-UX Workload Manager? |
|
|
HP-UX Workload Manager (WLM) is a resource management tool that assesses resource usage in real time and then automatically allocates resources and manages application performance based on your preferred service-level objectives (SLOs) and business priorities. WLM plays a key role in the HP Adaptive Enterprise and virtualization strategies, allowing hardware, software applications, and virtual server resources to be pooled and shared to optimize utilization and meet demands automatically. As a goals-based policy engine of the Virtual Server Environment (VSE), WLM integrates virtualization techniques—including partitioning, resource management, clustering, and utility pricing resources—and links them to the SLOs and business priorities. WLM enables a virtual HP-UX server to grow and shrink automatically based on the demands and SLOs for each application it hosts. By optimizing resource utilization in accord with SLOs and business priorities, WLM helps enterprises achieve greater return on their IT investment while ensuring that end-users receive the service and performance levels they expect. Some key uses of HP-UX WLM include:
You can use WLM within a whole server that can be clustered in an HP Serviceguard high availability cluster, Extended Campus Cluster, Metrocluster, or Continentalcluster. You can also use WLM on an HP Integrity Virtual Machines (Integrity VM) Host and within any individual Integrity VM (guest). You can use WLM within nPartitions and virtual partitions as well as across partitions. WLM is most effective managing applications that are CPU-bound. It adjusts the CPU allocation of the group of processes that constitute a workload, basing adjustment on current needs and performance of that workload’s applications. CPU resources can be allocated in shares (portions or time slices) of multiple cores or, when using WLM partition management or PSET management, in whole cores. WLM supports the logical CPU (Hyper-Threading) feature, which is available starting with HP-UX 11i v3 (B.11.31) for processors designed to support the feature and that have the appropriate firmware installed. A logical CPU is an execution thread contained within a core. Each core with Hyper-Threading enabled can contain multiple logical CPUs. WLM supports the Hyper-Threading feature for PSET-based groups. WLM automatically sets the Hyper-Threading state for the default PSET to optimize performance. (The default PSET, also known as PSET 0, is where all FSS groups reside.) When new PSETs are created, they inherit the Hyper-Threading state that the system had before WLM was activated (inheritance is based on the system state prior to WLM activation because WLM may change the Hyper-Threading setting for the default PSET to optimize performance). Cores can be moved from one partition to another and will take on the Hyper-Threading state of their destination PSET. To explicitly enable or disable Hyper-Threading for a PSET-based group, thereby overriding the default state for cores assigned to that group, specify the LCPU keyword with the PSET group definition in the prm structure. You can also modify the Hyper-Threading state of the system. For more information, see “Specifying workload groups (optional)” and wlmconf(4). WLM is optimized for moving cores across hosts such as nPartitions and virtual partitions. Using hosts as workloads, WLM manages workload allocations while maintaining the isolation of their HP-UX instances. WLM automatically moves (or “virtually transfers”) cores among partitions based on the SLOs and priorities you define for the workloads. With virtual partitions, WLM can automatically balance resources across the partitions. For example, if a processor is not being utilized within one virtual partition, WLM can deallocate it and reassign it to an alternate virtual partition that currently requires additional resources. With nPartitions, the cores are not physically moved. Instead, HP Instant Capacity software (formerly known as iCOD) simulates the movement of cores between partitions by deactivating cores on one nPartition, then activating cores on another nPartition. For information on managing SLOs across partitions, see Chapter 7 “Managing SLOs across partitions”. WLM can manage nested workloads (based on FSS groups and PSETs) inside virtual partitions that are inside nPartitions. Information on nested management is provided in Chapter 8 “Management of nested nPars / vPars / workload groups”. For each host (nPartition or virtual partition) workload, you define one or more SLOs in the WLM configuration file. WLM allows you to prioritize the SLOs so that an SLO assigned a high priority is given precedence over SLOs with a lower priority. Once configured, WLM then automatically manages CPU resources to satisfy the SLOs for the workloads. In addition, you can integrate WLM with HP Serviceguard to allocate resources in a failover situation according to defined priorities (for more information on integrating with HP Serviceguard, see “Integrating with Serviceguard”). You can also use WLM to manage workloads to divide resources within a single HP-UX instance by managing workloads based on Fair Share Scheduler (FSS) groups or processor sets (PSETs). Such workloads are usually referred to as workload groups.
When you configure WLM, you define workload groups for the system or partition and assign processes to the groups based on the specific applications, users, or Unix groups the processes run under. You can also create your own criteria for placing application processes in specified workload groups by defining process maps. In a process map, you map a group to a script or command and its arguments that gathers process IDs and causes the identified processes to be placed in that group. WLM spawns the command or script at 30-second intervals, and at each interval, places the identified processes in the appropriate groups. In addition, the WLM SAP Toolkit, in conjunction with HP Serviceguard Extension for SAP (SGeSAP), takes advantage of process maps, providing a script that enables you to place specified SAP processes in specific workload groups managed by WLM. For more information, see “Integrating with SAP software”. You can assign secure compartments to workload groups, creating the secure compartments with the HP-UX feature Security Containment. Secure compartments isolate files and processes. WLM can then automatically allocate resources for these secure compartments. When you configure WLM, you define one or more SLOs for each workload group and prioritize them. To satisfy the SLOs for the workload groups, WLM will then automatically manage CPU resources and, optionally, real memory and disk bandwidth (WLM management of workload groups is confined within the HP-UX instance or partition; no allocation is made across partitions.) If multiple users or applications within a workload group are competing for resources, standard HP-UX resource management determines the resource allocation within the workload. With real memory, WLM allows you to specify lower and upper limits on the amount of memory a workload group receives. Disk bandwidth shares can be statically assigned in the configuration file.
WLM can manage the following resources for your workloads:
In addition, WLM has an application manager that ensures that the following specified processes run in the appropriate workload groups:
|
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
 Printable version |
|
|
|
|
|
|||||||||||||||
|
|||||||||||||||
