From the above - there is insufficient space in the tenured generation to fit all objects in the eden-space and one survivor-space (if they were all live) - so the young generation is shown as the same size before and after the collection - the tenured collection removes around 54MB of objects - but the total post-collection space used (126223K) is the same figure as the tenured post-collection space used, so ...
QUESTIONS : IS THE YOUNG GENERATION NOW EMPTY ? IF SO, WHAT HAPPENED TO THE "YOUNG" OBJECTS ? HAVE THEY ALL BEEN PROMOTED ?
environment details -------------------
I'm running in WebSphere AppServer Version 5.1 (java version 1.4.2_03)
The min and max heap sizes are both 512MB, and with no "new size" parameters specified the young generation is being sized at 169600KB.
The gc params are as follows ... -XX:+PrintGCTimeStamps -XX:+PrintGCDetails
subject: GC - Young generation promotion can't be guaranteed