PARALLEL_MIN_SERVERS Does Not Limit The Number Of Parallel Processes At Startup in 12c
(Doc ID 1678111.1)
Last updated on FEBRUARY 23, 2024
Applies to:
Oracle Database - Enterprise Edition - Version 12.1.0.2 to 12.1.0.2 [Release 12.1]Oracle Database - Enterprise Edition - Version 12.1.0.1 to 12.1.0.1 [Release 12.1]
Oracle Database Cloud Schema Service - Version N/A and later
Gen 1 Exadata Cloud at Customer (Oracle Exadata Database Cloud Machine) - Version N/A and later
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Information in this document applies to any platform.
Symptoms
Setting the value of parallel_min_servers in 12c to a value lower than the default causes this parameter to be ignored:
Default value of PARALLEL_MIN_SERVERS in DB is 4*2*2 = 16 ------------------------------------------------------------ SQL> show parameter PARALLEL_MIN_SERVERS NAME TYPE VALUE ------------------------------------ ------------- --------- parallel_min_servers integer 16 Number of parallel processes is 16 ------------------------------------------------------------ [oracle@cdcjp81vm6 ~]$ ps -ef|grep ora_p0 oracle 3028 1 0 15:16 ? 00:00:00 ora_p000_db12c ...... oracle 3086 1 0 15:16 ? 00:00:00 ora_p00f_db12c 16 rows. Modified PARALLEL_MIN_SERVERS to 8, and restart database. ------------------------------------------------------------ SQL> alter system set PARALLEL_MIN_SERVERS = 8; System altered. SQL> shutdown immediate ...... SQL> startup ORACLE instance started. Database opened. PARALLEL_MIN_SERVERS was changed to 8, but the number of parallel processes was 16 as before. ------------------------------------------------------------ SQL> show parameter PARALLEL_MIN_SERVERS NAME TYPE VALUE ------------------------------------ ---------- --------- parallel_min_servers integer 16 SQL> exit Disconnected from Oracle Database 12c Enterprise Edition Release 12.1.0.1.0 - 64bit Production With the Partitioning, OLAP, Advanced Analytics and Real Application Testing options [oracle@cdcjp81vm6 ~]$ ps -ef|grep ora_p0 oracle 4002 1 0 15:28 ? 00:00:00 ora_p000_db12c ...... oracle 4056 1 0 15:28 ? 00:00:00 ora_p00f_db12c 16 rows.
Changes
The same setting was working with 11g Release 2 but no longer does in 12c.
Cause
To view full details, sign in with your My Oracle Support account. |
|
Don't have a My Oracle Support account? Click to get started! |
In this Document
| Symptoms |
| Changes |
| Cause |
| Solution |
| References |