Before validation, my memory usage is 63MB. My object graph consists of approximately 200K objects.

With my scenario, Hibernate Validator 5.0.1.Final gets an OutOfMemoryError at -Xmx512m, but succeeds at -Xmx1024m.
Our more comprehensive test case has a graph of up to 10 million objects, and fails at -Xmx8g.
My validators don't contain state, and the OOM errors do not have my validators in the call stack.

Is there anything I can do to reduce Hibernate Validator memory usage? The alternative would be for me to implement my own validator implementation that finds annotated classes, runs the appropriate validators, and packages its own ConstraintViolations, but I think you'll agree that that would be a pretty bad outcome.

I should note that if I remove all custom validators, I don't have a memory usage issue. This is true even if the validators all use default violation generation. To me, this implies that Hibernate Validation is doing something inappropriate and different with custom validators that it doesn't do with stock validators.

Hi,

That's interesting and I agree that this doesn't look right. Its hard to say whats the reason is without having some more details though.

Could you create an issue with our JIRA tracker (https://hibernate.atlassian.net/browse/HV), attaching a test case which shows the issue? Or if you could pass a heap dump that'd help as well. Have you tried using a tool such as Eclipse MAT (http://www.eclipse.org/mat/) to analyze the heap structure when an OOME occurs?

Thanks,

--Gunnar