Re: doc: vacuum full, fillfactor, and "extra space"

Hello Justin,

> I started writing this patch to avoid the possibly-misleading phrase: "with no
> extra space" (since it's expected to typically take ~2x space, or 1x "extra"
> space).
>
> But the original phrase "with no extra space" seems to be wrong anyway, since
> it actually follows fillfactor, so say that.  Possibly should be backpatched.

Patch applies and compiles.

Given that the paragraph begins with "Plain VACUUM (without FULL)", it is 
better to have the VACUUM FULL explanations on a separate paragraph, and 
the fillfactor precision makes it explicit about what it does, although it 
could also be material for the NOTES section below.

-- 
Fabien.