64-bit JVM support on solaris?

pclark · Post by **pclark** » Wed Oct 20, 2004 9:46 pm

When running a jvm with the -d64 flag on solaris (and probably other 64-bit platforms as well), the JVM exits just about immediately, reporting the following:

Error occurred during initialization of VM
Could not find -Xrun library: libyjpagent.so

I assume that this is because the agent library is a 32-bit binary, and you can't load 32-bit libraries into a 64-bit process. Any chance of creating a 64-bit version of the agent for solaris?

Thu Oct 21, 2004 10:26 am

Definitely not in 3.1. Most probable it will be implemented in the next major version.

BTW, what are the benefits of using 64bit Java? AFAIK, 32bit is a default mode and vast majority of Solaris programs are 32bit (only kernel drivers are 64 bit)

pclark · Post by **pclark** » Thu Oct 21, 2004 8:01 pm

The only reason I care about 64-bit java is that a client of mine is using JNI to integrate with some C code that runs in 64-bit mode, so we need to use a 64-bit JVM. We've been exploring this on solaris/sparc, linux and 64-bit windows on itanium and AMD64.

Post by **Vladimir Kondratyev** » Fri Oct 22, 2004 5:33 am

Just curious, did you see any performance gain with 64bit Java on Solaris/Sparc and Linux/ADM64?

pclark · Post by **pclark** » Sat Oct 23, 2004 3:23 am

No - generally it's slower, at best, it's just as fast. However, the library that we're integrating creates some very, very large data structures (> 4gb), and for that library, being able to directly address more than 4gb of memory does give us huge performance gains - the alternative is to build a swapping system and partition the data. As above, that library is in C, not Java; but we need it to be callable from Java code.

For pure java apps that don't need tons of memory, there's really no reason to do 64-bit java.

Post by **Anton Katilin** » Sat Oct 23, 2004 12:08 pm

Hi,

Thanks a lot for the detailed description.

We'll consider 64-bit Solaris support in the next major version.