Begin from v2.7, the ResourceManager Cluster Applications REST API returns ResourceRequest list. It's a very large construction in AppInfo.
As a test, we use below URI to query only 2 results:
http://<rm http address:port>/ws/v1/cluster/apps?states=running,accepted&limit=2
The results are very different:
|Hadoop version||Total Character||Total Word||Total Lines||Size|
Most RESTful API requesters don't know about this after upgraded and their old queries may cause ResourceManager more GC consuming and slower. Even if they know this but have no idea to reduce the impact of ResourceManager except slow down their query frequency.
The patch adding a query parameter "showResourceRequests" to help requesters who don't need this information to reduce the overhead. In consideration of compatibility of interface, the default value is true if they don't set the parameter, so the behaviour is the same as now.