On Wed, Jun 6, 2018 at 1:13 PM, Jeremy Finzel <finzelj@xxxxxxxxx> wrote:
On Wed, Jun 6, 2018 at 12:12 PM, Tom Lane <tgl@xxxxxxxxxxxxx> wrote:Jeremy Finzel <finzelj@xxxxxxxxx> writes:
> We have an odd scenario on one of our OLTP systems, which behaves the same
> way on a streamer, of a 700-1000ms planning time for a query like this:
> SELECT *
> FROM table1
> WHERE source_id IN (SELECT id FROM table2 WHERE customer_id = $1);
Hm. Is this the first query executed in a session? If so maybe it's
got something to do with populating caches and other session spin-up
overhead.
Another theory is it's some sort of locking issue. Turning on
log_lock_waits, and setting deadlock_timeout to say 100ms, would help
in investigating that.
regards, tom lane
I have run it over and over with no improvement in the planning time, so I don't thing it's first in session-related. I can only make it faster with a pl function so far.We have log_lock_waits on and nothing shows, and turning down deadlock_timeout also doesn't do anything.Thanks,Jeremy
Forgot to mention, this is running on this version:
PostgreSQL 9.6.8 on x86_64-pc-linux-gnu (Ubuntu 9.6.8-1.pgdg16.04+1), compiled by gcc (Ubuntu 5.4.0-6ubuntu1~16.04.9) 5.4.0 20160609, 64-bit
Thanks,
Jeremy
