Because I have 10.6 in production :) and I am comparing with what I will be loosing. And I read that in the release notes but as said in my first email, even with data_sync_retry=on (going back to previous behavior) doesn't make any difference.
So I am looking for something that will keep my performances but still allows me to upgrade to 11 in production. Also, trying with 11.1, the problem seems still there. Il giorno lun 4 mar 2019 alle ore 14:45 Imre Samu <pella.s...@gmail.com> ha scritto: > > is there any reason why I am getting worse results using pgsql11.2 in > writing comparing it with pgsql 10.6? > >... And Yes both are compiled. > > Why 10.6? > > according to release notes > "14th February 2019: PostgreSQL 11.2, 10.7, 9.6.12, 9.5.16, and 9.4.21 > Released!" https://www.postgresql.org/about/news/1920/ > 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"* > > Imre > > > > Nicola Contu <nicola.co...@gmail.com> ezt írta (időpont: 2019. márc. 4., > H, 13:14): > >> I did a analyze in stages on both. >> And Yes both are compiled. >> This is the configure command (change 10.6 for PG10) >> >> ./configure --prefix=/usr/local/pgsql11.2 >> >> See attached perf report. The difference seems to be all in this line, >> but not sure : >> >> + 26.80% 0.00% 222 postmaster [kernel.kallsyms] >> [k] system_call_fastpath >> >> >> >> I am using CentOS 7 >> With Centos I am using this profile for tuned-adm >> [root@STAGING-CMD1 ~]# tuned-adm active >> Current active profile: latency-performance >> >> >> Il giorno sab 2 mar 2019 alle ore 20:41 Thomas Munro < >> thomas.mu...@gmail.com> ha scritto: >> >>> On Sat, Mar 2, 2019 at 5:02 AM Ray O'Donnell <r...@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? >>> >>> -- >>> Thomas Munro >>> https://enterprisedb.com >>> >>
