Re: should INSERT SELECT use a BulkInsertState?

> On 4 Jun 2020, at 19:30, Andres Freund <andres@anarazel.de> wrote:
> On 2020-05-08 02:25:45 -0500, Justin Pryzby wrote:

>> Seems to me it should, at least conditionally.  At least if there's a function
>> scan or a relation or ..
>
> Well, the problem is that this can cause very very significant
> regressions. As in 10x slower or more. The ringbuffer can cause constant
> XLogFlush() calls (due to the lsn interlock), and the eviction from
> shared_buffers (regardless of actual available) will mean future vacuums
> etc will be much slower.  I think this is likely to cause pretty
> widespread regressions on upgrades.
>
> Now, it sucks that we have this problem in the general facility that's
> supposed to be used for this kind of bulk operation. But I don't really
> see it realistic as expanding use of bulk insert strategies unless we
> have some more fundamental fixes.

Based on the above, and the lack of activity in the thread, it sounds like this
patch should be marked Returned with Feedback; but Justin: you set it to
Waiting on Author at the start of the commitfest, are you working on a new
version?

cheers ./daniel