Re: ArrayLists instead of List (for some things)

On 2 November 2017 at 22:17, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> David Rowley <david(dot)rowley(at)2ndquadrant(dot)com> writes:
>> Comments on the design are welcome, but I was too late to the
>> commitfest, so there are other priorities. However, if you have a
>> strong opinion, feel free to voice it.
>
> I do not like replacing Lists piecemeal; that's a recipe for ongoing
> API breakage and back-patching pain. Plus we'll then have *four*
> different linked-list implementations in the backend, which sure
> seems like too many.
>
> We've jacked up the List API and driven a new implementation underneath
> once before. Maybe it's time to do that again.

I know some systems use hybrid linked array-lists, where linked list
cells are multi-element.

https://en.wikipedia.org/wiki/Unrolled_linked_list

I don't have much experience with them myself.

--
Craig Ringer http://www.2ndQuadrant.com/
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