Justin, Thanks for the quick response, I'll check it out. Happy holidays, Haroldo Kerry
On Thu, Dec 27, 2018 at 2:55 PM Justin Pryzby <pry...@telsasoft.com> wrote: > On Thu, Dec 27, 2018 at 02:44:55PM -0200, Haroldo Kerry wrote: > > PostgreSQL 9.6.10 on x86_64-pc-linux-gnu (Debian 9.6.10-1.pgdg80+1), > > > Connected to SAN: Dell Compellent SC2020, with 7 x Samsung PM1633 SSDs > > > https://www.samsung.com/us/labs/pdfs/collateral/pm1633-prodoverview-2015.pdf > , > > RAID10+RAID5 configuration, 8GB Cache, read-write battery backed cache > > enabled, connected via dedicated iSCSI switches and dedicated Ethernet > > ports, in link aggregation mode (2x1Gbps max bandwidth). > > > I’m trying to figure out if PostgreSQL (PG) has some inherent limit on > IOPS > > per connection. > > postgres uses one server backend per client. > > > We tried to increase effective_io_size from 1 to 30, to no effect on > > multiple tests. > > > https://www.postgresql.org/docs/current/runtime-config-resource.html#RUNTIME-CONFIG-RESOURCE-ASYNC-BEHAVIOR > => "Currently, this setting only affects bitmap heap scans." > > > Is this some inherent limitation of PG or am I misunderstanding > something? > > It is a hsitoric limitation, but nowadays there's parallel query, which > uses > 2ndary "backend worker" processes. > > It's supported in v9.6 but much more versatile in v10 and v11. > > Justin > -- Haroldo Kerry CTO/COO Rua do Rócio, 220, 7° andar, conjunto 72 São Paulo – SP / CEP 04552-000 hke...@callix.com.br www.callix.com.br
