Confio Software

Problem

Some customers have experienced problems with the new Ignite Top Plans feature.  The symptoms of the problems are errors in the Ignite error log similar to:

Error retrieving Plan Hashes for batch 1: ORA-12152: TNS:unable to send break message       

Other errors may accompany this problem and trace files may also be generated.  The likely cause of the problem is Oracle Bug 6356566 that affects STATSPACK and other tools along with Ignite.

Workaround

The workaround for this problem is to setup a logon trigger on the monitored database for the Ignite user to set a session level variable.

1. Pause the automatic monitor restart feature in the Ignite GUI. To do this, click the "Scheduler" button in the Ignite toolbar and change the "Repository Scheduling Status" setting to "Paused".

2. Stop the Ignite monitor for the database

3. Log into the monitored database as SYSTEM (or some DBA user) and create the trigger with the code below.

4. Restart the monitor for the database and re-enable the automatic scheduler (opposite of Step 1).

Trigger Code

CREATE OR REPLACE TRIGGER ignite_logon_trg
AFTER LOGON ON DATABASE
BEGIN
   IF UPPER(USER) = UPPER('&IgniteUser') THEN
      EXECUTE IMMEDIATE 'ALTER SESSION SET "_cursor_plan_unparse_enabled" = FALSE';
   END IF;
END;
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