Yes its 128MB, the default.
You raise an interesting point, Peter.
Just to clarify we were using shared_buffers=30GB for our initial pgbench runs that would take a few hours to complete. In an attempt to make the tests repeatable before submitting I have simplified the steps.
I have updated the testing rigs to use 40GB of shared buffers with the same results. :(
--------------
demo_server.postgres $ for p in 9500 11000; do echo "* DB ON PORT $p *"; /usr/pgsql-11/bin/psql -Upostgres -qp $p -f create_table.sql; /usr/pgsql-11/bin/psql -Upostgres -qtp $p -c"show shared_buffers"; /usr/pgsql-11/bin/pgbench -Upostgres -f insert.sql -n -c 60 -j 60 -T120 postgres -p $p;/usr/pgsql-11/bin/psql -Upostgres -qtp $p -c"select 'table size = ' || pg_size_pretty(pg_total_relation_size('test_indexes'))"; done
* DB ON PORT 9500 *
40GB
transaction type: insert.sql
scaling factor: 1
query mode: simple
number of clients: 60
number of threads: 60
duration: 120 s
number of transactions actually processed: 4493742
latency average = 1.602 ms
tps = 37447.000308 (including connections establishing)
tps = 37449.413044 (excluding connections establishing)
table size = 581 MB
* DB ON PORT 11000 *
40GB
transaction type: insert.sql
scaling factor: 1
query mode: simple
number of clients: 60
number of threads: 60
duration: 120 s
number of transactions actually processed: 3606004
latency average = 1.997 ms
tps = 30049.353360 (including connections establishing)
tps = 30052.041139 (excluding connections establishing)
table size = 467 MB
On Tue, 12 Feb 2019 at 13:49, Peter Geoghegan <
pg@bowt.ie> wrote:
On Mon, Feb 11, 2019 at 4:47 PM Saul, Jean Paolo
<paolo.saul@verizonconnect.com> wrote:
> Aside from the ports:
>
> listen_addresses = '*'
> max_connections = 300
> max_wal_senders = 0 -- (on PG11)
> synchronous_commit = off
You mean shared_buffers is set to the default?
I don't think that that's an interesting test case. If shared_buffers
is ridiculously small, then there is little that we can take away from
your benchmark, or any benchmark like it.
--
Peter Geoghegan
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