I can tell you this is very obvious on the mac OSX platform. Much less so on the Windows platform but still was evident. With the improvements to the use of Java for LW 4.9 recently, these have reduced but still exist in some form at least. For mac osx, it included large ram use & large virtual memory (temp storage on HDD.) AFAIK this is fundamentally a Java flaw. Java unfortunately doesn't release the memory it holds down as quickly as it should. Later versions of Java improve upon this but still it's an issue at least with the most recent Java despite the improvements. And for LW, despite the nio improvements it still affects some people though not so badly.