While running the camunda build including the unit tests repeatedly on my Windows workstation I saw a dramatic resource and run time increasement ending in failures in "engine plugins - identity - ldap" tests.
Similar problems I saw before when running the tests on a Solaris SPARC box.
This is caused by the temporary files created by this testsuite.
On my Windows workstation stored in C:\Users\Frank\AppData\Local\Temp (dirs server-work and ldap-posix-work and files replica* and jffi*). On Solaris it's /var/tmp.
If I delete this files and dirs before running the build, all is fine.
If those files stay and second run is done, the tests need much more time (5 - 10 times more) or have failures. While tests are running, CPU and Memory usage are at 100%.

Those mentioned files and dirs should be deleted either during clean or during build before ldap tests are run or after ldap tests have finished.