Re: Enable huge_pages in PostgreSQL server version 11.2

You havent mentioned what is the amount of huge pages that you have
configured. Make sure that is slightly higher than the shared_buffer value.
We usually set shared_buffer to 8GB and set the huge pages to 5120 (i.e.
5120 pages of 2mb so a total of 10gb). Setting it exactly to 4096 does not
work.

On Mon, 12 Aug 2019 at 19:18, Suresh Seema <suresh(dot)seema(at)opsveda(dot)com> wrote:

> Hi Everyone,
>
> We have installed PostgresSQL 11.2 version on Centos 7 and we want
> perform PG benck mark with huge_pages with size of 2MB and 1GB.
> We have modified required kernel parameters ,grub configuration and set
> the huge page count in OS Level .But Postgresql instance is not starting
> with *huge_pages = on* parameters but working with huge_pages = try.
> When we run test with huge_pages = try db parameter huge pages not getting
> utilized.
>
> *Please find PG instance configuration below : *
> *-------------------------*
> max_connections = 200
> shared_buffers = 60GB
> effective_cache_size = 70GB
> maintenance_work_mem = 1024MB
> default_statistics_target = 500
> random_page_cost = 1.2
> effective_io_concurrency = 1000
> work_mem = 256MB
> max_worker_processes = 32
> max_parallel_workers_per_gather = 16
> max_parallel_workers = 32
> enable_parallel_append = on
> enable_parallel_hash = on
> force_parallel_mode = off
> min_parallel_index_scan_size = 64
> min_parallel_table_scan_size = 512
> parallel_leader_participation = off
> parallel_setup_cost = 100
> parallel_tuple_cost = 0.1
> cpu_tuple_cost = 0.01
> temp_buffers = 512MB
> huge_pages = on # on, off, or try
>
> Error:
> # systemctl status postgresql
> ● postgresql.service - PostgreSQL 11 database server
> Loaded: loaded (/usr/lib/systemd/system/postgresql.service; enabled;
> vendor preset: disabled)
> Active: failed (Result: exit-code) since Mon 2019-08-12 11:52:19 UTC;
> 10min ago
> Docs: https://www.postgresql.org/docs/11/static/
> Process: 6882 ExecStart=/usr/pgsql-11/bin/postmaster -D ${PGDATA}
> (code=exited, status=1/FAILURE)
> Process: 6868 ExecStartPre=/usr/pgsql-11/bin/postgresql-11-check-db-dir
> ${PGDATA} (code=exited, status=0/SUCCESS)
> Main PID: 6882 (code=exited, status=1/FAILURE)
>
> Aug 12 11:52:19 ip-10-1-4-103.ec2.internal postmaster[6882]: 2019-08-12
> 11:52:19.433 UTC [6882] LOG: listening on IPv6 addres... 5432
> Aug 12 11:52:19 ip-10-1-4-103.ec2.internal postmaster[6882]: 2019-08-12
> 11:52:19.434 UTC [6882] LOG: listening on Unix socket...5432"
> Aug 12 11:52:19 ip-10-1-4-103.ec2.internal postmaster[6882]: 2019-08-12
> 11:52:19.438 UTC [6882] LOG: listening on Unix socket...5432"
> Aug 12 11:52:19 ip-10-1-4-103.ec2.internal postmaster[6882]: 2019-08-12
> 11:52:19.441 UTC [6882] FATAL: could not map anonymou...emory
> Aug 12 11:52:19 ip-10-1-4-103.ec2.internal postmaster[6882]: 2019-08-12
> 11:52:19.441 UTC [6882] HINT: This error usually means tha...
> Aug 12 11:52:19 ip-10-1-4-103.ec2.internal postmaster[6882]: 2019-08-12
> 11:52:19.442 UTC [6882] LOG: database system is shut down
> Aug 12 11:52:19 ip-10-1-4-103.ec2.internal systemd[1]: postgresql.service:
> main process exited, code=exited, status=1/FAILURE
> Aug 12 11:52:19 ip-10-1-4-103.ec2.internal systemd[1]: Failed to start
> PostgreSQL 11 database server.
> Aug 12 11:52:19 ip-10-1-4-103.ec2.internal systemd[1]: Unit
> postgresql.service entered failed state.
> Aug 12 11:52:19 ip-10-1-4-103.ec2.internal systemd[1]: postgresql.service
> failed.
> Hint: Some lines were ellipsized, use -l to show in full.
>
> *Please suggest me on this . *
>
>
> --
> Regards,
> Suresh Seema
>