Memory Leaks When Destroying Tables

[kraftp]

I'm observing memory leaks when creating and destroying tables, even when closing all connections properly. Here is some example code:

    MonetDBEmbeddedDatabase.startDatabase(":memory:");
    int numRows = 10000000;
    int[] one = new int[numRows];
    int[] two = new int[numRows];
    int[] three = new int[numRows];
    Object[] cols = new Object[]{one, two, three};

    for (int i = 0; i < 1000; i++) {
        MonetDBEmbeddedConnection embeddedConnection = MonetDBEmbeddedDatabase.createConnection();
        embeddedConnection.executeUpdate("CREATE TABLE t (one int, two int, three int)");
        MonetDBTable t = embeddedConnection.getMonetDBTable("t");
        t.appendColumns(cols);
        t.close();
        embeddedConnection.executeUpdate("DROP TABLE t");
        embeddedConnection.close();
    }

Even though this code destroys every table immediately after creation, when run it will rapidly consume all available memory then crash. It appears that memory consumed by tables populated by appendColumns is not freed when the tables are destroyed. I have not observed this behavior with tables populated in other ways.

[PedroTadim]

This was a known issue fixed on Jun2020 release. This shall be fixed when MonetDBe gets ported to Java. However I can backport it to the current MonetDBLite version.

[PedroTadim]

MonetDBe-Java has been released: https://github.com/MonetDBSolutions/MonetDBe-Java