Hi,
I'm experiencing consistent session hangs when using Oracle SQL Developer for VS Code (v26.2.0) connected to an Oracle database.
The issue occurs when:
- Running simple dictionary queries like:
SELECT * FROM dba_free_space WHERE tablespace_name = '...';
- Or compiling packages (ALTER PACKAGE ... COMPILE BODY)
Symptoms:
- The query/compile appears to run forever.
- In v$session, the session is in WAIT on event "PX Deq: Execute Reply".
- v$lock shows multiple "Parallel operation locks" in Share mode for the session.
- Parallel slaves (P000, P001, etc.) are created.
- The blocking session is reported as the parallel slave itself (P000).
Example from v$session for my hanging session:
SID SERIAL# SQL_ID EVENT WAIT_CLASS STATE BLOCKING_SESSION BLOCKING_SESSION_STATUS SECONDS_IN_WAIT
579 8819 374bk6zwnn8d6 PX Deq: Execute Reply Idle WAITING 589 VALID 156
Investigation already done:
- PARALLEL_DEGREE_POLICY is MANUAL at session level.
- However, parallel slaves are still created.
- The wait is not on a data lock or row lock, but on the parallel execution coordinator waiting for slave replies.
Workaround that works:
Run before the problematic operation:
ALTER SESSION DISABLE PARALLEL QUERY;
ALTER SESSION DISABLE PARALLEL DML;
ALTER SESSION DISABLE PARALLEL DDL;
After this, the queries and compiles complete normally.
Environment:
- Oracle SQL Developer for VS Code: 26.2.0
- OS: Windows
- Oracle Database version: 19c
Question:
Is there a way to prevent SQL Developer for VS Code from triggering parallel execution by default?
Or is there a known issue with this extension spawning parallel slaves that then hang waiting for each other?
I would prefer not to have to manually disable parallel execution for every session.
Thanks for any guidance.