Re: One process per session lack of sharing

Craig>That moves work further away from the DB, which has its own costs,
and isn't something you're likely to be happy with if you're looking at
things like optimising PL/PgSQL with a bytecode compiler. But it's the best
we have right now.

What if JVM was started within a background worker?
Then JVM can spawn several threads that serve PL requests on a "thread per
backend" basis.

Craig>You may be able to greatly reduce that cost if you can store your
cached compiled data in a shared memory segment created by your extension.
Craig>This will get a bit easier with the new dynamic shared memory
infrastructure, but it's going to be no fun at all to make that play with
the JVM. You'll probably need a lot of JNI.

There's https://github.com/jnr/jnr-ffi that enables to call C functions
without resorting to writing JNI wrappers.

Vladimir