Tuning the proportion of importance given to status information
The manager uses ratios to determine the importance of status information coming from advisors and Load Balancer. You can change the default ratios that the manager uses to weight this information.
About this task
- Active connections: The number of active connections on each load balanced server machine (as tracked by the executor), or
- CPU (in the case of the Site Selector component, based on input from the Metric Server)
- New connections: The number of new connections on each load balanced server machine (as tracked by the executor), or
- Memory (in the case of the Site Selector component, based on input from the Metric Server)
- Port-specific: The input from advisors listening on the port.
- System metric: The input from the system monitoring tools, such as Metric Server or WLM.
Along with the current weight for each server and some other information required for its calculations, the manager gets the first two values (active and new connections) from the executor. These values are based on information that is generated and stored internally in the executor.
- When adding an advisor (other than WLM), if the port proportion is zero, then the manager increases this value to 1. Because the sum of the relative proportions must total 100, the highest value is then decreased by 1.
- When adding the WLM advisor, if the system metric proportion is zero, then the manager increases this value to 1. Because the sum of the relative proportions must total 100, the highest value is then decreased by 1.
The number of active connections is dependent upon the number of clients as well as the length of time necessary to use the services that are being provided by the load balanced server machines. If the client connections are quick (such as small Web pages served using HTTP GET), then the number of active connections are fairly low. If the client connections are slower (such as a database query), then the number of active connections are higher.
You should avoid setting active and new connections proportions values too low. You will disable load balancing and smoothing unless you have these first two values set to at least 20 each.
Procedure
dscontrol cluster set cluster proportions value
See
the topic on the dscontrol cluster command
for more information.