Category: Database

Server Process,”Oracle creates server processes to handle the requests of user processes connected to the instance. In some situations when the application and Oracle operate on the same machine, it is possible to combine the user process and corresponding server process into a single process to reduce system overhead. However, when the application and Oracle operate on different machines, a user process always communicates with Oracle through a separate server process.Server processes (or the server portion of combined user/server processes) created on behalf of each user’s application can perform one or more of the following:Parse and run SQL statements issued through the applicationRead necessary data blocks from datafiles on disk into the shared database buffers of the SGA

Database

Average Rating 0 out of 5 stars. 0 votes.You must log in to submit a review.Server Process,”Oracle creates server processes[…]

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PMON or Process monitorback,”Monitors the other background processes and performs process recovery when a server or dispatcher process terminates abnormallyPMON periodically performs cleanup of all the following:*Processes that died abnormally*Sessions that were killedtimeout*Detached network connections which have exceeded their idle timeoutIn addition, PMON monitors, spawns

Database

Average Rating 0 out of 5 stars. 0 votes.You must log in to submit a review.PMON or Process monitorback,”Monitors the[…]

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SMON or System Monitor Processback,”Performs critical tasks such as instance recovery and dead transaction recovery, and maintenance tasks such as temporary space reclamation, data dictionary cleanup, and undo tablespace managementSMON performs many database maintenance tasks, including the following:* Creates and manages the temporary tablespace metadata* Reclaims space used by orphaned temporary segments* Maintains the undo tablespace by onlining, offlining, and shrinking the undo segments based on undo space usage statistics* Cleans up the data dictionary when it is in a transient and inconsistent state* Maintains the SCN to time mapping table used to support Oracle Flashback featuresIn an Oracle RAC database

Database

Average Rating 0 out of 5 stars. 0 votes.You must log in to submit a review.SMON or System Monitor Processback,”Performs[…]

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Snn or Shared Server Processback,”Handles client requests in the shared server architecture.In the shared server architecture, clients connect to a dispatcher process, which creates a virtual circuit for each connection. When the client sends data to the server, the dispatcher receives the data into the virtual circuit and places the active circuit on the common queue to be picked up by an idle shared server. The shared server then reads the data from the virtual circuit and performs the database work necessary to complete the request. When the shared server must send data to the client, the server writes the data back into the virtual circuit and the dispatcher sends the data to the client. After the shared server completes the client request, the server releases the virtual circuit back to the dispatcher and is free to handle other clients.Several initialization parameters relate to shared servers. The principal parameters are: DISPATCHERS, SHARED_SERVERS, MAX_SHARED_SERVERS, LOCAL_LISTENER

Database

Average Rating 0 out of 5 stars. 0 votes.You must log in to submit a review.Snn or Shared Server Processback,”Handles[…]

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