oracle 数据库 processes、sessions 的设置

os: centos 7.4
db: oracle 11.2.0.4

版本

# cat /etc/centos-release
CentOS Linux release 7.4.1708 (Core) 

# su - oracle
Last login: Mon Jul 13 14:42:54 CST 2020 on pts/0
$ 
$ 
$ sqlplus / as sysdba;

SQL*Plus: Release 11.2.0.4.0 Production on Mon Jul 13 14:50:33 2020

Copyright (c) 1982, 2013, Oracle.  All rights reserved.


Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, Real Application Clusters, Automatic Storage Management, OLAP,
Data Mining and Real Application Testing options

SQL> set lines 200;
set pages 200;

SQL> select * from v$version;

BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
PL/SQL Release 11.2.0.4.0 - Production
CORE	11.2.0.4.0	Production
TNS for Linux: Version 11.2.0.4.0 - Production
NLSRTL Version 11.2.0.4.0 - Production

processes、sessions

当前的值

SQL> show parameter processes;
processes			     integer			      1000

SQL> show parameter sessions; 
sessions			     integer			      1528

SQL> alter system set processes=600 scope=spfile;

SQL> startup force;

SQL> show parameter processes;
processes			     integer			      600

SQL> show parameter sessions;
sessions			     integer			      928

sessions 值随着 sessions自动调整

sessions= processes * 1.5 + 28

下面单独设置下 sessions

SQL> alter system set sessions = 1000 scope=spfile;

SQL> startup force;

SQL> show parameter processes;
processes			     integer			      600

SQL> show parameter sessions;
sessions			     integer			      1000

可以看到 sessions单独设置1000后，显示为1000

所以日常运维中只需要设置 processes 参数即可。