No, it was wrong.
At Mon, 29 Aug 2016 17:08:36 +0900 (Tokyo Standard Time), Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp> wrote in
<20160829.170836.161449399.horiguchi.kyotaro@lab.ntt.co.jp>
> Hello,
>
> I considered applying the async infrastructure onto nodeGather,
> but since parallel workers hardly make Gather (or the leader)
> wait, it's really useless at least for simple cases. Furthermore,
> as several people may have said before, being defferent from
> foreign scans, gather (or other kinds of parallel) nodes usually
> have several workers and will have up to two digit nubmers at the
> most even on so-called many-core boxes. I finally gave up
> applying this to nodeGather.
I overlooked that local scan takes place instead of waiting
workers to be ready. I will reconsider counting that..
> As the result, the attached patchset is functionally the same
> with the last version but replace misused Assert with
> AssertMacro.
--
Kyotaro Horiguchi
NTT Open Source Software Center