Class data sharing on windows not working if I set large heap size



Setting a heap size larger than about 27MB causes class data sharing to
fail (I know this because I have set '-Xshare:on' to force the JVM to
use it).

Does anyone know why this is the case?

Do I need to set the -Xmx parameter when regenerating the classes.jsa
file? Sun's documentation implies that the windows classes.jsa file is
always the same, so it doesn't ever need regenerating.

.