You can set an upper limit to the number of index worker threads for a Content Platform Engine instance. By doing so, you control the indexing work capacity of the instance.
Maximum workers per CPE instance = upper limit * (running CSS servers / configured CSS servers)
In this calculation, CPE instance refers to a Content Platform Engine instance, and server refers to an IBM Content Search Services index server. Configured CSS servers includes all registered index servers that have a status of either UNAVAILABLE or ENABLED (that is, any status other than DISABLED). Running CSS servers includes all configured servers that have a status of ENABLED. For example, suppose that you register four index servers with Content Platform Engine, enable them, and set the upper limit to 20. In the normal situation, all configured servers are running, and the calculated maximum number of worker threads is the same as the upper limit: 20 * (4 / 4) = 20. Otherwise, if not all configured servers are running, the calculated maximum is some fraction of the upper limit. For instance, if only three index servers are running, the calculated maximum is 15: 20 * (3 / 4) = 15.
To set the upper limit for the maximum number of worker threads of a subsystem dispatcher: