Issue
A Java application will throw a java.lang.StackOverflowError when a thread of execution consumes all of the memory available to that thread's stack. This usually results from a very deep method call stack.
In most cases, this error is caused by infinite recursion (a problem with your application code), but it is sometimes caused by a legitimately large use of a thread's stack. On Heroku's Eco, Basic, (formerly Hobby), and Standard-1X dynos the default Java thread stack size is 512 KB (-Xss512k), which overrides the default JVM setting of 1 MB. This difference may cause an app to work locally, but throw a java.lang.StackOverflowError on the smaller Heroku dyno sizes.
Resolution
You can increase the thread stack size on Heroku by adding the -Xss1m option to your Procfile. For example:
web: java -Xss1m -jar target/myapp.jar
Any JVM options in the Procfile will override the defaults set by Heroku.
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