Collect Thread Dump and Heap Dump on Linux App Service (Java/Tomcat)

The following steps can be followed for both our Java and Tomcat offerings on Linux App Service. Note that, if you are using a custom image, you could enable webSSH and collect dumps using jcmd, if present.

1. Go to the Kudu Site of the WebApp via Advanced Tools blade:

2. Click on SSH to ssh into the Application Container:

3. Get the PID of the Java Process (your application):

[There are multiple ways to get it. We can use ps -ef | grep java | grep -v grep command, or simply run jcmd]

4. Finally, execute the following command to collect the Thread Dump and save it as a file. 

jcmd <PID of Java Process> Thread.print > /home/threaddump

Similarly, to collect the heap dump, run:

jcmd <PID of Java Process> GC.heap_dump /home/heapdump

Note:

The files under /home are only persistent by default. Consider collecting the dumps under /home or in the mounted location for External Storage (if using BYOS)