Neoview Workload Management Services Guide (R2.5)

Table 4-1 Predefined HPS Services and Rules (continued)
Associated Connection RulesPredefined Services
HPS_MANAGEABILITY9HPS_MANAGEABILITY
HPS_MANAGEABILITY10
HPS_MANAGEABILITY11
HPS_TRANSPORTER1HPS_TRANSPORTER
Default Service
By default, WMS uses the default service, HP_DEFAULT_SERVICE, to handle incoming queries.
As an administrator, you can alter the thresholds of HP_DEFAULT_SERVICE but cannot delete
this service.
User-Defined Services
As an administrator, you can define your own services to distribute query workloads according
to your workload management strategy. You may add up to 255 user-defined services in addition
to the predefined HP_DEFAULT_SERVICE, HPS_MANAGEABILITY, HPS_TRANSPORTER,
and SYSTEM services on a Neoview platform. For more information, see “Configure WMS
Services” (page 54).
How Do Services Work?
Each service in WMS has a priority, system resource thresholds, and active time associated with
it:
• “Service Priority” (page 48)
• “System Resource Thresholds” (page 48)
• “Active Time” (page 49)
Service Priority
The priority of a service determines when the queries associated with the service start to execute
in relation to queries associated with other services. If queries from low and high priority services
are waiting to execute, the high priority queries start to execute before the low priority queries,
provided that the system resource usage does not reach its limits.
The service priority is not a runtime or process priority. The service priority serves as a launch
priority, determining when the queries in a service are launched from the waiting queue into
execution relative to other services. The service priority is not associated with the process priorities
of the SQL components involved in query execution, such as the master executor (or NDCS
server), executor server processes (ESPs), and SQL compiler. Each of the SQL components involved
in the execution of a query has its own process priority. Those process priorities can be changed
to influence the execution priority of the query. To set the process priorities, please contact your
HP Support representative for assistance.
System Resource Thresholds
The system resource thresholds, MAX_CPU_BUSY and MAX_MEM_USAGE, of a service influence
whether incoming queries associated with the service start executing immediately or are put in
a waiting queue. To determine available CPU and memory resources for the Neoview platform,
WMS looks at a moving average every five seconds for six intervals of CPU busy and takes a
snapshot every five seconds of memory usage on the Neoview platform. When the system
resource usage reaches the threshold limits for the service, WMS puts incoming queries associated
with the service into a waiting queue.
48 Configuring Services