APM Support can only provide limited and general guidance on Agent load testing. Instead seek guidance in the APM Development Community Group.
We are seeing an issue with the performance of our IIS Sharepoint application when we run load test of 30K+ users when CA APM is instrumented. The symptoms include worker threads being maxed out as well at CPU topping out resulting in a failed test.
When we remove CA APM from the servers and perform the same load test the results are acceptable.
What is the level of overhead we should be expecting when CA APM is instrumented?
This was tested with
- an APM 10.5.1 EM
- an APM 10.3 agent
But can apply to any release.
The customer successfully reached 40,000 login sessions by doing the following
1) Disabling the Sharepoint agent.
2) Following the steps in https://docops.ca.com/ca-apm/10-3/en/ca-apm-sizing-and-performance/agent-performance/
3) Change config settings
a) Set introscope.agent.sockets.reportRateMetrics=false
It has talks about turning off the following
c) Enable/disable tracking in the monitored code for Application Map
introscope.agent.appmap.enabled=false. You may need this functionality
# Change to this property takes effect immediately and do not require the managed application to be restarted.
d) Other properties
What sort of load impact that the Sharepoint extension should have? It should be low impact around 5-15% of the baseline