permission denied for function pg_ls_waldir

We observed the below PMM agent log alerts in the PMM server.

PMM agent log:

==========

agentID=/agent_id/be09d7c1-6b62-4c0a-b1d7-19f2af019646 component=agent-process type=postgres_exporter
time="2023-12-13T12:07:33.116+00:00" level=error msg="ts=2023-12-13T12:07:33.116Z caller=collector.go:202 level=error msg=\"collector failed\" name=wal duration_seconds=0.013273851 err=\"pq: permission denied for function pg_ls_waldir\"" agentID=/agent_id/be09d7c1-6b62-4c0a-b1d7-19f2af019646 component=agent-process type=postgres_exporter
time="2023-12-13T12:07:38.111+00:00" level=error msg="ts=2023-12-13T12:07:38.110Z caller=collector.go:202 level=error msg=\"collector failed\" name=wal duration_seconds=0.007016725 err=\"pq: permission denied for function pg_ls_waldir\"" agentID=/agent_id/be09d7c1-6b62-4c0a-b1d7-19f2af019646 component=agent-process type=postgres_exporter
time="2023-12-13T12:07:43.114+00:00" level=error msg="ts=2023-12-13T12:07:43.114Z caller=collector.go:202 level=error msg=\"collector failed\" name=wal duration_seconds=0.010718618 err=\"pq: permission denied for function pg_ls_waldir\"" agentID=/agent_id/be09d7c1-6b62-4c0a-b1d7-19f2af019646 component=agent-process type=postgres_exporter
time="2023-12-13T12:07:48.104+00:00" level=error msg="ts=2023-12-13T12:07:48.104Z caller=collector.go:202 level=error msg=\"collector failed\" name=wal duration_seconds=0.000585894 err=\"pq: permission denied for function pg_ls_waldir\"" agentID=/agent_id/be09d7c1-6b62-4c0a-b1d7-19f2af019646 component=agent-process type=postgres_exporter
time="2023-12-13T12:07:53.110+00:00" level=error msg="ts=2023-12-13T12:07:53.110Z caller=collector.go:202 level=error msg=\"collector failed\" name=wal duration_seconds=0.006203611 err=\"pq: permission denied for function pg_ls_waldir\"" agentID=/agent_id/be09d7c1-6b62-4c0a-b1d7-19f2af019646 component=agent-process type=postgres_exporter

postgresql14.log:

===========

2023-12-13 11:56:13.108 UTC [27525] ERROR:  permission denied for function pg_ls_waldir
2023-12-13 11:56:13.108 UTC [27525] STATEMENT:  
            SELECT
                COUNT AS segments,
                SUM(size) AS size
            FROM pg_ls_waldir()
            WHERE name ~ '^[0-9A-F]{24}$'
2023-12-13 11:56:18.104 UTC [27586] ERROR:  permission denied for function pg_ls_waldir
2023-12-13 11:56:18.104 UTC [27586] STATEMENT:  
            SELECT
                COUNT AS segments,
                SUM(size) AS size
            FROM pg_ls_waldir()
            WHERE name ~ '^[0-9A-F]{24}$'
2023-12-13 11:56:23.124 UTC [27667] ERROR:  permission denied for function pg_ls_waldir
2023-12-13 11:56:23.124 UTC [27667] STATEMENT:  
            SELECT
                COUNT AS segments,
                SUM(size) AS size
            FROM pg_ls_waldir()
            WHERE name ~ '^[0-9A-F]{24}$'
2023-12-13 11:56:28.112 UTC [27740] ERROR:  permission denied for function pg_ls_waldir
2023-12-13 11:56:28.112 UTC [27740] STATEMENT:  
            SELECT
                COUNT AS segments,
                SUM(size) AS size
            FROM pg_ls_waldir()
            WHERE name ~ '^[0-9A-F]{24}$'
2023-12-13 11:56:33.104 UTC [27850] ERROR:  permission denied for function pg_ls_waldir
2023-12-13 11:56:33.104 UTC [27850] STATEMENT:  
            SELECT
                COUNT AS segments,
                SUM(size) AS size
            FROM pg_ls_waldir()
            WHERE name ~ '^[0-9A-F]{24}$'
2023-12-13 11:56:38.104 UTC [27909] ERROR:  permission denied for function pg_ls_waldir
2023-12-13 11:56:38.104 UTC [27909] STATEMENT:  
            SELECT
                COUNT AS segments,
                SUM(size) AS size
            FROM pg_ls_waldir()
            WHERE name ~ '^[0-9A-F]{24}$'
2023-12-13 11:56:43.106 UTC [27960] ERROR:  permission denied for function pg_ls_waldir
2023-12-13 11:56:43.106 UTC [27960] STATEMENT:  
            SELECT
                COUNT AS segments,
                SUM(size) AS size
            FROM pg_ls_waldir()
            WHERE name ~ '^[0-9A-F]{24}$'
2023-12-13 11:56:48.109 UTC [28168] ERROR:  permission denied for function pg_ls_waldir
2023-12-13 11:56:48.109 UTC [28168] STATEMENT:  
            SELECT
                COUNT AS segments,
                SUM(size) AS size
            FROM pg_ls_waldir()
            WHERE name ~ '^[0-9A-F]{24}$'