why is jvm throwing "unrecognized option" when i use "-d64"?

Question

I'm setting up my JAVA_OPTS with: "-d64 -server -XX:+CMSClassUnloadingEnabled" and then some.

I thought the -d64 was to specify that the machine was 64bit or running on 64bit!?

This seems to work fine on Macs. When I tried it on Windows 7 using Cygwin to run the shell script, it breaks. If I remove the -d64, everything works fine.

I also did the same thing using windows batch files, the -d64 still throw the same error.

What could be the problem?

Answer 1

The -d64 option is Solaris/Linux specific. On Windows that option is not available

As Mac OsX is linux-based, the option would work there. On Windows you will need to select the JVM by selecting the executable (the 64 bit/32 bit versions are separate installation) -- either directly naming the executable or by properly adding its bin to the PATH environmental variable