Re: Performance comparison between Pgsql 10.5 and Pgsql 11.2

> 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(dot)contu(at)gmail(dot)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(at)STAGING-CMD1 ~]# tuned-adm active
> Current active profile: latency-performance
>
>
> Il giorno sab 2 mar 2019 alle ore 20:41 Thomas Munro <
> thomas(dot)munro(at)gmail(dot)com> ha scritto:
>
>> 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
>>
>