Issue on space . Disk space increases and decreases automatically

Hi All,

In our QA environment for past 2 days we are facing issue on space . some unusual behaviour. Taken threaddumps at that time and found the issue

"172.30.104.53 [1373723166026] <closed>" daemon prio=3 tid=0x0000000101dca800 nid=0x135f in Object.wait() [0xfffffffd8a9ff000]

   java.lang.Thread.State: WAITING (on object monitor)

        at java.lang.Object.wait(Native Method)

        - waiting on <0xfffffffdf9743658> (a com.day.j2ee.servletengine.HttpListener$Worker)

        at java.lang.Object.wait(Object.java:485)

        at com.day.j2ee.servletengine.HttpListener$Worker.await(HttpListener.jav a:587)

        - locked <0xfffffffdf9743658> (a com.day.j2ee.servletengine.HttpListener$Worker)

        at com.day.j2ee.servletengine.HttpListener$Worker.run(HttpListener.java: 612)

        at java.lang.Thread.run(Thread.java:662)

Please let me know where exact issue on thread.