PROCESSES specifies the maximum number of operating system user processes that
can simultaneously connect to Oracle. Its value should allow for all background
processes such as locks, job queue processes, and parallel execution processes.
The default values of the SESSIONS and TRANSACTIONS parameters are derived from
this parameter.
设置processes会对share_pool process 池有一定的影响,当修改时可以对比一下修改前后的share_pool process的变化
select * from v$sgastat where pool='shared pool' and name='processes';
设置可以参照
所有连接池最大连接数+ all background processes + parallel execution processes+用户需要的连接