Bare Metal Java

BEA has replaced the OS layer that lives with the VMware VM below it and BEA’s JRockit JVM above it by writing some 60K lines of code for an “OS shim” that responds to memory allocations, JVM thread requests and a few housekeeping chores.

This shim has an API layer (based on POSIX), so that it can be ported in the future to other platforms. (It does not support a filesystem, curiously. Files are expected to all be accessed remotely on networked storage. More on the internals of the shim can be found at developers.sun.com/learning/javaoneonline/2006/coolstuff/TS-3792.pdf, which makes for great reading.)

The combined VM/OS shim/JRockit JVM is being shipped as a single unit, or as BEA calls it, a software appliance—the BEA LiquidVM. When you add BEA’s application server, the bundle is called WebLogic Server, Virtual Edition (WLVE). The benefit of WLVE is that you can configure the app server for the Liquid VM software appliance and then move it around your infrastructure as you need it.