Re: Performance comparison between Pgsql 10.5 and Pgsql 11.2

On Sat, Mar 2, 2019 at 5:02 AM Ray O'Donnell <ray(at)rodonnell(dot)ie> wrote:
> On 01/03/2019 15:01, Nicola Contu wrote:
> > Hello,
> > is there any reason why I am getting worse results using pgsql11.2 in
> > writing comparing it with pgsql 10.6?
> >
> > I have two Instances, both just restored, so no bloats.
> > Running read queries I have pretty much same results, a little bit
> > better on pg11- Running writes the difference is in favour of 10.
>
> Did you run ANALYZE on the databases after restoring?

If you can rule out different query plans, and if you compiled them
both with the same compiler and optimisation levels and without
cassert enabled (it's a long shot but I mentioned that because you
showed a path in /usr/local so perhaps you're hand-compiling 11, but
10 came from a package?), then the next step might be to use a
profiler like "perf" (or something equivalent on your OS) to figure
out where 11 is spending more time in the write test?

--
Thomas Munro
https://enterprisedb.com