On Tue, Apr 27, 2021 at 9:31 PM Etsuro Fujita <etsuro.fuj...@gmail.com> wrote: > On Mon, Apr 26, 2021 at 7:35 PM Andrey V. Lepikhov > <a.lepik...@postgrespro.ru> wrote: > > Small mistake i found. If no tuple was received from a foreign > > partition, explain shows that we never executed node.
> > The patch in the attachment fixes this. > > Will look into this. The patch fixes the issue, but I don’t think it’s the right way to go, because it requires an extra ExecProcNode() call, which wouldn’t be efficient. Also, the patch wouldn’t address another issue I noticed in EXPLAIN ANALYZE for async-capable nodes that the command wouldn’t measure the time spent in such nodes accurately. For the case of async-capable node using postgres_fdw, it only measures the time spent in ExecProcNode() in ExecAsyncRequest()/ExecAsyncNotify(), missing the time spent in other things such as creating a cursor in ExecAsyncRequest(). :-(. To address both issues, I’d like to propose the attached, in which I added instrumentation support to ExecAsyncRequest()/ExecAsyncConfigureWait()/ExecAsyncNotify(). I think this would not only address the reported issue more efficiently, but allow to collect timing for async-capable nodes more accurately. Best regards, Etsuro Fujita
fix-EXPLAIN-ANALYZE-for-async-capable-nodes.patch
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