But in case of critical issues in the app, like sudden application slowness, where you haven't installed APM Insight agent previously and an application restart would mean losing the issue at hand, you can use the below suggested method to install the agent without a restart. This would enable you to identify the issue at hand without restarting your application.
Note:We DO NOT recommend this method of installation until it is necessary. Also, kindly avoid this method when your JVM has low free memory or high CPU usage. Loading the Java agent via this approach would consume high memory & CPU for a short period during initialization.
Download the agent zip file from SIte24x7 web client (APM > APM Insight > Java).
Extract the agent zip anywhere on the machine. Ensure that the user running the app server has read-write permission over this directory.
Identify the app server Process ID (PID) that needs to be monitored.
Execute the following command from the agent directory: java -jar apminsight-javaagent.jar -start PID
Note: This installation works only one time. If you restart your application, you won't be able to see the monitoring data again. In such cases, we recommend you to install the APM Insight agent following the usual installation procedure.