| Instances per database |
Maximum number of cluster database instances per database |
Operating system-dependent |
| Locks |
Row-level |
Unlimited |
| Locks |
Distributed Lock Manager |
Operating system dependent |
| 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 |
| Advanced Queuing Processes |
Maximum per instance |
10 |
| Job Queue Processes |
Maximum per instance |
1000 |
| I/O Slave Processes |
Maximum per background process (DBWR, LGWR, etc.) |
15 |
| I/O Slave Processes |
Maximum per Backup session |
15 |
| Sessions |
Maximum per instance |
32 KB; limited by the PROCESSES and SESSIONS initialization parameters |
| Global Cache Service Processes |
Maximum per instance |
10 |
| Shared Servers |
Maximum per instance |
Unlimited within constraints set by the PROCESSES and SESSIONS initialization parameters, for instance |
| Dispatchers |
Maximum per instance |
Unlimited within constraints set by PROCESSES and SESSIONS initialization parameters, for instance |
| Parallel Execution Slaves |
Maximum per instance |
Unlimited within constraints set by PROCESSES and SESSIONS initialization parameters, for instance |
| Backup Sessions |
Maximum per instance |
Unlimited within constraints set by PROCESSES and SESSIONS initialization parameters, for instance |