A.4 Process and Runtime Limits

This table describes limit types and limit values for process and runtime items.

Item Type of Limit Limit Value

Advanced Queuing Processes

Maximum per instance

10

Backup Sessions

Maximum per instance

Limited by the PROCESSES and SESSIONS initialization parameters, for instance

Dispatchers

Maximum per instance

Limited by the PROCESSES and SESSIONS initialization parameters, for instance

Global Cache Service Processes

Maximum per instance

10

Instances per database

Maximum number of cluster database instances per database

Operating system-dependent

I/O Worker Processes

Maximum per background process (DBWR, LGWR, and so on)

15

I/O Worker Processes

Maximum per Backup session

15

Job Queue Processes

Maximum per instance

1000

Locks

Distributed Lock Manager

Operating system dependent

Locks

Row-level

Not defined

Parallel Execution Workers

Maximum per instance

Limited by the PROCESSES and SESSIONS initialization parameters, for instance

Services

Maximum per instance

8200

Sessions

Maximum per instance

218 - 1, which is 262143; limited by the PROCESSES and SESSIONS initialization parameters.

SGA size

Maximum value

Operating system-dependent; typically 2 to 4 GB for 32-bit operating systems, and > 4 GB for 64-bit operating systems

Shared Servers

Maximum per instance

Limited by the PROCESSES and SESSIONS initialization parameters, for instance