Re: shared-memory based stats collector

At Tue, 16 Mar 2021 16:44:38 +0900 (JST), Kyotaro Horiguchi <horikyota(dot)ntt(at)gmail(dot)com> wrote in
> At Mon, 15 Mar 2021 19:04:29 -0700, Andres Freund <andres(at)anarazel(dot)de> wrote in
> > Do you have some benchmarks that you used to verify performance?
>
> https://www.postgresql.org/message-id/20201008.160326.2246946707652981235.horikyota.ntt%40gmail.com
>
> It is using pgbench, with 800 clients with 20 threads.
>
> Graphs of performance gain/loss from the master for the following
> benchmarks are attached.
>
> > - Fetching 1 tuple from 1 of 100 tables from 100 to 800 clients.
> > - Fetching 1 tuple from 1 of 10 tables from 100 to 800 clients.
>
> v36 showed about 60% of degradation (TPS redued to 1/3 of master) at
> 600 clients, but it has been dissapeared as of v39. The graphs are of
> v39. I'm asking for the script that was used for the benchark and will
> send them later.

This is that.

create_tables.sh: creates tables for benchmarking.
simple_use_file_ac_1000.sql: randomly selects 1 tuple from a table.

$ createdb benchdb
$ ./create_tables.sh benchdb 100000 # the case of 100000 tables
$ pgbench benchdb -n -c100 -j20 -T300 -r P 10 -f simple_use_file_ac_1000.sql

regards.

--
Kyotaro Horiguchi
NTT Open Source Software Center