"Reached the maximum number of concurrent connections" issue with OPartitionedDatabasePool and its working behavior

[arpitdd123]

Hello,

While performing some operations on the OrientDB, I faced issue for OrientDB connection.
In my code, I am getting ODatabaseDocument using OPartitionedDatabasePool and then at the end trying to close
ODatabaseDocument and OPartitionedDatabasePool. But it seems that connection are not getting closed.

So I tried same with below POC code.

Case 1: Connections are not getting closed

public class NonWorkingCloseConnection {
    public static void main(String[] args) {
        String databaseUrl = "url";
        String userName = "username";
        String password = "password";
        OPartitionedDatabasePool pool = new OPartitionedDatabasePool(databaseUrl, userName, password);
        ODatabaseDocument oDatabaseDocument = pool.acquire();
         if (Objects.nonNull(pool) && Objects.nonNull(oDatabaseDocument)) {
            oDatabaseDocument.activateOnCurrentThread();
			oDatabaseDocument.close();
            pool.close();
        }
    }
}

After executing the code, I observed that when calling oDatabaseDocument.close(); followed by pool.close();, no binary listeners were closed. I have verified this, through the OrientDB Studio Server Management UI. These connections are released only after code execution thread is terminated.

As a result after creating many connections, OrientDB console logs the following message: "Reached the maximum number of concurrent connections (max=1000, current=1000), rejecting incoming connection from /127.0.0.1:54782 [OServerNetworkListener]".

Case 2: Connections are getting closed by reversing the API order

After reversing the order, first calling pool.close(); and then oDatabaseDocument.close(); the binary listener associated with oDatabaseDocument instance getting successfully closed.

public class WorkingCloseConnection {
    public static void main(String[] args) {
        String databaseUrl = "url";
        String userName = "username";
        String password = "password";
        OPartitionedDatabasePool pool = new OPartitionedDatabasePool(databaseUrl, username, password);
        ODatabaseDocument oDatabaseDocument = pool.acquire();
         if (Objects.nonNull(pool) && Objects.nonNull(oDatabaseDocument)) {
			oDatabaseDocument.activateOnCurrentThread();
			pool.close();
            oDatabaseDocument.close();
        }
    }
}

This behavior is observed on all the OrientDB versions.
Is closing the pool before closing the oDatabaseDocument instance the correct approach?

[ikysil]

hi @arpitdd123

Could you please add the version of the OrientDB your are using for these tests.
Do you observe the same behavior when using version 3.2.38 vs 3.2.39+?

Check #10453

[arpitdd123]

Hello @ikysil,
We faced this issue on OrientDB versions 3.2.3, 3.2.17, 3.2.21, 3.2.38 as well as 3.2.39.

[tglman]

Hi,

This case I think it is related to the use of the legacy OPartitionedDatabasePool we did have issue in the past with closing sessions with that specific instance, since 3.0.x we do suggest to use instead: https://orientdb.dev/docs/3.2.x/java/Document-API-Database.html?highlight=pool#using-database-pools