Troubleshooting OCI Database with PostgreSQL
Use troubleshooting information to identify and address common issues that can occur while working with OCI Database with PostgreSQL.
Extension Creation Fails with "Not Allowed" Error
When creating an extension in an OCI Database with PostgreSQL environment, you receive an error that the extension is not allowed.
Most extensions supported by OCI Database with PostgreSQL are available for immediate use, but some require an administrator to enable the extension through a custom configuration. For example, the pg_stat_statements extension might be listed as supported, but isn't immediately usable.
If you try to create the pg_stat_statements extension and it's not enabled by the administrator, you might see an error. For example:
postgres=> CREATE EXTENSION pg_stat_statements;
ERROR: Extension : pg_stat_statements is not allowed
To check if an extension such as pg_stat_statements is available, you can see the pg_available_extensions catalog, which shows the latest extensions and their version information. For example:
postgres=> SELECT * FROM pg_available_extensions WHERE name = 'pg_stat_statements';To see which extensions are enabled for your tenancy by administrators, use oci.admin_enabled_extensions. For example:
postgres=> SHOW oci.admin_enabled_extensions;
oci.admin_enabled_extensions
------------------------------
postgres_fdw
(1 row)
If pg_stat_statements isn't listed, it means it's not enabled yet.
Memory Utilization Remains High While the Database System is Idle
OCI Database with PostgreSQL metrics show high memory utilization, even when the database system is idle.
OCI Database with PostgreSQL does its own memory management using a custom page cache. OCI Database with PostgreSQL pre-allocates a fixed amount of memory for this custom page cache and doesn't use it for any other purposes.
With default settings, about 75% of the total memory of the database system is always allocated for oci.pagecache and shared_buffers. OCI Database with PostgreSQL Metrics show this amount as used, but this memory is used for PostgreSQL data buffers as intended and doesn't result in any negative effects.
For more information, see oci.pagecache_size.