You can perform common memory diagnostics or shared memory diagnostics based on your business requirements.

Common memory

Check the polar_stat_activity_rt view to obtain memory details. The following code provides an example:
SELECT pid, rss
FROM polar_stat_activity_rt 
ORDER BY rss
DESC; \watch 1
Then, you can use the polar_backends_mcxt view to check the memory context that occupies the most memory space in the process.
Note No details about memory contexts of PolarDB for PostgreSQL(Compatible with Oracle) are provided. To further analyze memory context, you must use kernel code or SQL statements.

Shared memory

You can view the distribution of shared memory in the polar_stat_shmem view.