On Wed, 29 Jul 2020 at 00:26, Scott Ribe <scott_ribe@xxxxxxxxxxxxxxxx> wrote: > But does compilation with JIT enable and LLVM dev tools mean that all the LLVM compilation/optimization is built into the PG binaries, or does it require LLVM presence on the machine where deployed? And if so, does the function take that into account as well? It's not enough for just the build to have been built with jit enabled. The jit extension must also be present on the machine. I think the new wording in https://www.postgresql.org/docs/devel/functions-info.html conveys that: "Returns true if a JIT compiler extension is available (see Chapter 31) and the jit configuration parameter is set to on." David