On Monday, December 20, 2021, Tom Lane <
tgl@sss.pgh.pa.us> wrote:
Justin Pryzby <pryzby@telsasoft.com> writes:
> On Mon, Dec 20, 2021 at 08:11:42PM -0800, Lars Bergeson wrote:
>> Still taking 10X more I/O to read the smaller table. Very odd.
> If I'm not wrong, it's even worse than that ?
> It takes 20 or 30sec to run the query - but it says the associated I/O times
> are ~500sec or ~6000sec ?
It would help if somebody had labeled the units of I/O Time
... but I'm guessing those are microsec vs. the millisec
of the other times, because otherwise it's completely wrong.
Related to my preceding observation, from the explain (buffers) docs:
“…and the time spent reading and writing data file blocks (in milliseconds) if track_io_timing is enabled.“
David J.