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 | 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 |