Spring Performance test may result in ConcurrentModificationException, less than 1% of requests will fail

I don't know why happened this exception,if too many request access, less than one percent of request will fail.

What should I do to solve the problem?

This is stack of exception:

Caused by: java.util.ConcurrentModificationException
    at java.util.LinkedHashMap$LinkedHashIterator.nextNode(LinkedHashMap.java:719) ~[?:1.8.0_232]
    at java.util.LinkedHashMap$LinkedEntryIterator.next(LinkedHashMap.java:752) ~[?:1.8.0_232]
    at java.util.LinkedHashMap$LinkedEntryIterator.next(LinkedHashMap.java:750) ~[?:1.8.0_232]
    at java.util.HashMap.putMapEntries(HashMap.java:512) ~[?:1.8.0_232]
    at java.util.HashMap.putAll(HashMap.java:785) ~[?:1.8.0_232]
    at org.springframework.web.servlet.view.AbstractView.createMergedOutputModel(AbstractView.java:341) ~[spring-webmvc-5.2.4.RELEASE.jar:5.2.4.RELEASE]
    at org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:314) ~[spring-webmvc-5.2.4.RELEASE.jar:5.2.4.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1373) ~[spring-webmvc-5.2.4.RELEASE.jar:5.2.4.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1118) ~[spring-webmvc-5.2.4.RELEASE.jar:5.2.4.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1057) ~[spring-webmvc-5.2.4.RELEASE.jar:5.2.4.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943) ~[spring-webmvc-5.2.4.RELEASE.jar:5.2.4.RELEASE]
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) ~[spring-webmvc-5.2.4.RELEASE.jar:5.2.4.RELEASE]
    ... 38 more

Comment From: sbrannen

I've edited your comment to improve the formatting. You might want to check out this Mastering Markdown guide for future reference.

Comment From: sbrannen

Please provide an example (preferably a project on GitHub or some other online repository that we can check out and build or a ZIP file that we can download and build) to demonstrate the behavior you are experiencing.

Thanks

Comment From: spring-projects-issues

If you would like us to look at this issue, please provide the requested information. If the information is not provided within the next 7 days this issue will be closed.

Comment From: spring-projects-issues

Closing due to lack of requested feedback. If you would like us to look at this issue, please provide the requested information and we will re-open the issue.