|  
 Instances per database 
 | 
 
 Maximum number of cluster database instances per database 
 | 
 
 Operating system-dependent 
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|  
 Locks 
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 Row-level 
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 Unlimited 
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|  
 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 
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 Maximum per instance 
 | 
 
 10 
 | 
|  
 Job Queue Processes 
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 Maximum per instance 
 | 
 
 1000 
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|  
 I/O Slave Processes 
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 Maximum per background process (DBWR, LGWR, etc.) 
 | 
 
 15 
 | 
|  
 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 
 |