Re: pgsql: Add documentation for the JIT feature.

On Thu, Mar 29, 2018 at 9:44 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> I'd go a little further and drop "JIT" from user-facing documentation
> altogether. Instead refer to the feature as "compilation of expressions"
> or some such. JIT is just jargon. Plus, the timing of the compilation is
> actually the least important property for our purpose.

I agree that talking about JIT compilation (or just-in-time
compilation) would be better than talking just about JIT, but refusing
to mention JIT seems counter-productive to me. There are a lot of
people who know what just-in-time compilation is and will not realize
that "compilation of expressions" refers to any such technology. If
you don't know what it is, you can Google it. Just typing "jit" into
Google produces a stupid urban dictionary hit and then this:
https://en.wikipedia.org/wiki/Just-in-time_compilation -- and that
contains useful information that you'll never find if you search for
"compilation of expressions".

Also, in a way, you could argue that v10 already did "compilation of
expressions". It didn't compile them to machine language, true, but
it translated them into a form which is faster to execute, and which
is at least arguably a form of bytecode. It's not going to be clear,
even to an expert, that "compilation of expressions" means something
other than that, but if you say JIT, then all of a sudden people know
what we're talking about.

I agree that JIT is jargon, but it's pretty commonly-used jargon.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company