WebSphere Application Server V8.5 Administration and Configuration Guide for the Full Profile

Chapter 18. Clustering and high availability 703

To use this variable for load balancing:

 Set the server_use_wlm_to_queue_work property to 0:

server_use_wlm_to_queue_work 0

 Set the server_work_distribution_algorithm to 0, 1 or 2, based on one of the following

settings:

0 - Hot Thread: In this case, each new work request is assigned to the first servant that

has a thread available to process the request. If none of the servants have an available

thread, the request is queued into the global work queue that is shared by all servants.

The request is then selected from the global work queue when the next thread becomes

available, regardless of which servant owns that thread.

1- Round Robin: In this case, new work requests are distributed evenly across all

servants. If all of the servant threads are already processing other work requests, the new

request is added to the request queue for a specific servant. The queued request is then

selected when it becomes the top request in the queue and a thread becomes available in

that servant.

2 - Hot Robin: In this case, new work requests are distributed evenly across all servants. If

the assigned servant does not have a thread available to process the request, the request

is reassigned to another servant that has an available thread. If none of the servants have

an available thread, the new request is queued into the global work queue that all of the

servants share. The request is then selected from the global work queue when the next

thread becomes available, regardless of which servant owns that thread.

We set the environment variable, server_use_wlm_to_queue_work, to zero, which implies

that work load management has a minimal role to play. With this variable setting, WLM does

not start additional servants, although WLM will still classify the work.

This arrangement works for both stateful and stateless applications.

18.5 Additional resources

For more information about high availability, consult the following resources:

 For more information about support for client reroute for applications that use DB2, go to

the following Information Center website:

hhttp://pic.dhe.ibm.com/infocenter/wasinfo/v8r5/index.jsp?topic=%2Fcom.ibm.webs

phere.zseries.doc%2Fae%2Ftdat_clientreroute.html

 To learn more about achieving node isolation with intermediate symbolic links, go to the

following website:

http://www-03.ibm.com/support/techdocs/atsmastr.nsf/WebIndex/WP100396

704 WebSphere Application Server V8.5 Administration and Configuration Guide for the Full Profile