JVM settings > 4GB memory store produce a Confluence crash when rendering PDF files with large images.

Steps to reproduce:

1. Configure a Confluence instance with > 4GB of memory
2. Attach Medusa.pdf to a page and embed it in a ViewFile macro
3. Save the page and Confluence will crawl to a halt and crash

The bug's behaviour appears to be identical to the CONF-30711 bug.
The workaround from the CONF-30711 bug doesn't work.

Possible Workaround one of customers reported that upgrading java to version 7u55 stabilised the instance from the occurrence of crashes.