imho: it would be better to compare PG11.2 with PG10.7 ( similar bug Fixes and Improvements + same fsync() behavior )
"This release changes the behavior in how PostgreSQL interfaces with fsync() and includes fixes for partitioning and over 70 other bugs that were reported over the past three months"
Il giorno sab 2 mar 2019 alle ore 20:41 Thomas Munro <thomas.munro@gmail.com> ha scritto:
On Sat, Mar 2, 2019 at 5:02 AM Ray O'Donnell <ray@rodonnell.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?
