Re: JIT compiling with LLVM v12.2 - Mailing list pgsql-hackers

From Andres Freund
Subject Re: JIT compiling with LLVM v12.2
Date
Msg-id 20180320231829.2dctywxip3f2nkvy@alap3.anarazel.de
Whole thread Raw
In response to Re: JIT compiling with LLVM v12.2  (Thomas Munro <thomas.munro@enterprisedb.com>)
List pgsql-hackers
Hi,

On 2018-03-21 12:07:59 +1300, Thomas Munro wrote:
> The documentation builds and the resulting HTML looks good, and I like
> what you've written for users and also for developers in the README
> file.

Cool.


> Perhaps it could use something about how to know it's working
> with EXPLAIN (or any other introspection there might be), but maybe
> you're still working on that?

I'd not yet seen that as a priority, but I think it'd make sense to show
an example of that.  Perhaps showing a select query from a function,
once with that function's cost set to the default, and once with it set
to something high?


> I did a proof-reading pass and have some minor language and
> typesetting suggestions.  See comments below and attached patch
> (against current HEAD of your jit branch) which implements all of
> these changes, which of course you can feel free to take individual
> hunks from or ignore if you disagree!

Yeha!


> +   <varlistentry>
> +    <term><acronym>JIT</acronym></term>
> +    <listitem>
> +     <para>
> +      <ulink url="https://en.wikipedia.org/wiki/Just-in-time_compilation">Just
> in Time
> +      Compilation</ulink>
> +     </para>
> +    </listitem>
> +   </varlistentry>
> 
> The usual typesetting seems to be "just-in-time" (with hyphens),
> including on Wikipedia, various literature and in dictionaries.  Here
> "compilation" doesn't seem to need a capital letter (it's not part of
> the acronym, it's not otherwise in a title context where
> capitalisation is called for).

I wasn't sure about that one, thanks.



> +     <varlistentry id="guc-jit-above-cost" xreflabel="guc-jit-above-cost">
> 
> xreflabel should use underscores not hyphens, and shouldn't have the
> leading "guc" (this breaks the resulting HTML).

Oops, yea, that's definitely a mistake.


> +        Sets the planner's cutoff after which JIT compilation is used as part
> ...
> +        Sets the planner's cutoff after which JIT compiled programs (see <xref
> 
> s/after which/above which/.  I see there was some nearby text that
> used "after which", but that was talking about time.
> 
> I think writers might do s/JIT compiled/JIT-compiled/ here and some
> similar places (JIT-generated, JIT-accelerated etc), though I'm not
> sure about that and I doubt anyone cares so I didn't change it.

I was wondering about that...


Thanks a lot for going through this!

Greetings,

Andres Freund


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