Postgres EF2 querying group errors

[Yosi_Neuman]

Hi guys,

Customer installed Postgres EF2 and see the follows errors in logs 

[59fe9974-0efc-3f6b-b9f1-0c0f2899e878][1270370671638307859][4772][out][59fe9974-0efc-3f6b-b9f1-0c0f2899e878]2024-08-13 | 11:16:43.046 | pool-5-thread-1      | ERROR | c.d.s.p.p.AbstractPoller  | While polling from endpoint ServerName:PortNum:postgres, querying group 'pg_stat_statements_topn_14+' failed
[59fe9974-0efc-3f6b-b9f1-0c0f2899e878][1270370671638307859][4772][out]org.apache.tomcat.jdbc.pool.PoolExhaustedException: [pool-5-thread-1] Timeout: Pool empty. Unable to fetch a connection in 30 seconds, none available[size:1; busy:1; idle:0; lastwait:30000].
[59fe9974-0efc-3f6b-b9f1-0c0f2899e878][1270370671638307859][4772][out]	at org.apache.tomcat.jdbc.pool.ConnectionPool.borrowConnection(ConnectionPool.java:741)
[59fe9974-0efc-3f6b-b9f1-0c0f2899e878][1270370671638307859][4772][out]	at org.apache.tomcat.jdbc.pool.ConnectionPool.getConnection(ConnectionPool.java:199)
[59fe9974-0efc-3f6b-b9f1-0c0f2899e878][1270370671638307859][4772][out]	at org.apache.tomcat.jdbc.pool.DataSourceProxy.getConnection(DataSourceProxy.java:133)
[59fe9974-0efc-3f6b-b9f1-0c0f2899e878][1270370671638307859][4772][out]	at com.dynatrace.sql.jdbc.JdbcExecutor.getConnection(JdbcExecutor.java:136)
[59fe9974-0efc-3f6b-b9f1-0c0f2899e878][1270370671638307859][4772][out]	at com.dynatrace.sql.jdbc.JdbcExecutor.execute(JdbcExecutor.java:57)
[59fe9974-0efc-3f6b-b9f1-0c0f2899e878][1270370671638307859][4772][out]	at com.dynatrace.sql.polling.pollers.AbstractPoller.poll(AbstractPoller.java:79)
[59fe9974-0efc-3f6b-b9f1-0c0f2899e878][1270370671638307859][4772][out]	at com.dynatrace.sql.polling.pollers.TopNPoller.poll(TopNPoller.java:77)
[59fe9974-0efc-3f6b-b9f1-0c0f2899e878][1270370671638307859][4772][out]	at com.dynatrace.sql.polling.pollers.TopNPoller.lambda$schedulePolling$1(TopNPoller.java:103)
[59fe9974-0efc-3f6b-b9f1-0c0f2899e878][1270370671638307859][4772][out]	at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
[59fe9974-0efc-3f6b-b9f1-0c0f2899e878][1270370671638307859][4772][out]	at java.base/java.util.concurrent.FutureTask.runAndReset(Unknown Source)
[59fe9974-0efc-3f6b-b9f1-0c0f2899e878][1270370671638307859][4772][out]	at java.base/java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(Unknown Source)
[59fe9974-0efc-3f6b-b9f1-0c0f2899e878][1270370671638307859][4772][out]	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
[59fe9974-0efc-3f6b-b9f1-0c0f2899e878][1270370671638307859][4772][out]	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
[59fe9974-0efc-3f6b-b9f1-0c0f2899e878][1270370671638307859][4772][out]	at java.base/java.lang.Thread.run(Unknown Source)

We see in logs those errors for the follows groups:

•  'pg_stat_statements_topn'
• 'pg_stat_statements_topn_12-'
• 'pg_stat_statements_topn_14+'
• 'pg_stat_activity_aggregated'
• 'pg_stat_activity_longest'

Customer says there is no tables that he can see with those names 

Questions:

• From where those groups are coming?
• How can we eliminate those errors?  

Postgres version is 15.3

EF2 version is 2.2.2

Thanks in advance for your inputs

Yos 

[TomásSeroteRoos · Accepted solution]

Those are just the names of the groups in the extension. The extension actually goes to

pg_stat_statements for

• 'pg_stat_statements_topn'
• 'pg_stat_statements_topn_12-'
• 'pg_stat_statements_topn_14+'

pg_stat_activity for

• 'pg_stat_activity_longest'
• pg_stat_activity_aggregated

You can see this and the exact queries yourself by downloading the extension zip file for your version from the Dynatrace Hub and checking the extension.yaml file.

From the error message, the problem seems to be related to the connection from the AG to the database though... I would suggest opening a support ticket with Dynatrace so that they can have a look at the AG support archive and see exactly what's going on. This kind of problem can be tricky.

[Yosi_Neuman]

Thanks @TomásSeroteRoos 

We will open a support ticket 

Yos