I tried to access the API for the load statistics. The address for the graphical load statistics of the master node is http://jenkinshost/computer/(master)/load-statistics. However, http://jenkinshost/computer/(master)/load-statistics/api/xml returns me a HTTP404.

Via the API documentation at http://jenkinshost/computer/(master)/api/ I found that the machine readable data for the load statistics is accessible via http://jenkinshost/computer/(master)/loadStatistics/api/xml but the resulting XML file contains always no content for any section:

<loadStatistics>
<availableExecutors/>
<busyExecutors/>
<connectingExecutors/>
<definedExecutors/>
<idleExecutors/>
<onlineExecutors/>
<queueLength/>
<totalExecutors/>
</loadStatistics>

Perhaps the path loadStatistics was renamed to load-statistics some time ago?