Hi,
On 2026-03-31 20:03:02 +0200, Tomas Vondra wrote:
> On 3/31/26 19:41, Andres Freund wrote:
> > Hi,
> >
> > On 2026-03-30 20:21:29 +0200, Tomas Vondra wrote:
> >>>> From 410eaaebe7b814ac9f44c080e153f4ec1d6d6b86 Mon Sep 17 00:00:00 2001
> >>>> From: Tomas Vondra <tomas@vondra.me>
> >>>> Date: Thu, 19 Mar 2026 22:25:09 +0100
> >>>> Subject: [PATCH v5 3/6] explain: show prefetch stats in EXPLAIN (ANALYZE)
> >>>>
> >>>> This adds details about AIO / prefetch for executor nodes using a
> >>>> ReadStream. Right now this applies only to BitmapHeapScan, because
> >>>> that's the only scan node using a ReadStream and collecting
> >>>> instrumentation from workers.
> >>>
> >>> I don't understand why that means it should be done as part of this commit,
> >>> whereas seqscans shouldn't?
> >>>
> >>
> >> Are you suggesting the commit adds support for all those scans (BHS,
> >> SeqScan and TidRangeScan) or none of them?
> >
> > I guess I mostly just didn't quite understand what differentiates bitmap scans
> > from the other scans, based on this explanation.
> >
> >
> >> To me it seems better to have at least some scan because of testing. But
> >> SeqScan/TidRangeScan don't have the instrumentation infrastructure for
> >> parallel queries, and I don't want to do that in the main patch - it seems
> >> rather unrelated. And I also don't want to add it before the main patch.
> >
> > I'd probably do the latter, i.e. add it before the main patch. Or at least
> > separately from the change to show read stream instrumentation.
> >
>
> Sorry, I'm confused. Which "latter" option you mean?
Adding the instrumentation infrastructure for seqscan, tidscan as a separate
patch before the main commit.
Greetings,
Andres Freund
