Sunday, February 26, 2017

oracle Backup policy


Taleo does 3 actions to backup production zones in its standard backup policy.
Backup data is kept on disk storage.  Backup Policy (Doc ID 1046592.1)

Oracle RMAN

  • Used for short term backups (30 days retention).
  • One full backup a week. For most customers, this is done on Friday or Saturday.
  • Two incremental backups per week, usually on Tuesday / Thursday or on Wednesday / Friday.
  • 6 backups of archive logs (transactions) per day.
  • These backups allows for an exact point in time recovery to be performed.

Oracle Data Pump

  • A full database export usually performed on Friday (weekly).
  • 60 days retention.
  • Copied on Tier 2 (local) and Tier 3 storage locations.

Oracle Data Guard

  • All transactions replicated to physical standby databases in Data Replication sites.

Backup Restoration

  • A database recovery is a billable service and requires a Statement of Work (SOW). Communicate with the Client Success Specialist (CSS / CE) for more information on creating this SOW.
  • During a restore, all data on the target zone is replaced by the backup's. It is not possible to restore only specific entities; the whole schema is replaced when applying the backup.
  • Any change or new data between the time the backup was taken and the moment the restore is applied is lost.

most important guidelines regarding Data Pump compatibility


The following are the most important guidelines regarding Data Pump compatibility:
1. The compatibility level of the Data Pump dumpfile set is determined by the compatibility level of the source database.

2. Use the Export Data Pump client (expdp) that matches the version of the source database (up to one major version lower expdp client can be used, but this is not recommended).

3. Use the Import Data Pump client (impdp) that matches the version of the target database (up to one major version lower impdp client can be used, but this is not recommended).

4. Use the Export Data Pump parameter VERSION in case the target database has a lower compatibility level than the source database.

5. Transferring data over a database link is supported even if the compatibility level of the (remote) source database differs from the (local) connected database (up to one major version difference is supported).

6. Import Data Pump can always read Export Data Pump dumpfile sets created by older versions of the database.

7. Export dumpfiles created with the Export Data Pump client (expdp) cannot be read by the original Import client (imp).

8. Export dumpfiles created with the original Export client (exp) cannot be read by the Import Data Pump client (impdp).

Saturday, February 25, 2017

List of background Processes in Oracle Database 12c

Acronym

Process Name
Description
Required for basic DB operation
Started by default
New in this release
ABMR
Auto BMR Background Process
Coordinates execution of tasks such as filtering duplicate block media recovery requests and performing flood control.
No
No
No
APnn
Logical Standby / Streams Apply Process Coordinator Process
Obtains transactions from the reader server and passes them to apply servers
No
No
No
ARC 0..t
Archiver Process (30 possible)
Copies the redo log files to archival storage when they are full or an online redo log switch occurs
No
No
No
BMRn
Automatic Block Media Recovery Slave Pool Process
Fetches blocks from a real-time readable standby database
No
No
No
BW nn
Database Writer Process (20 possible)
Writes modified blocks from the database buffer cache to the data files. The names of the 37th through 100th Database Writer Processes are BW36-BW99. See DBWn for more information on these processes.
Yes
Yes
Yes
CJQ0
Job Queue Coordinator Process
Spawns slave processes (Jnnn) to execute jobs in the queue.
No
Yes
No
CKPT
Checkpoint Process
Signals DBWn at checkpoints and updates all the data files and control files of the database to indicate the most recent checkpoint
Yes
Yes
No
CPnn
Database Capture Process
Captures database changes from the redo log by using the infrastructure of LogMiner.
No
No
No
CSnn
Streams Propagation Sender Process
Sends LCRs to a propagation receiver.
No
No
No
CSnn
I/O Calibration Process
Issues I/Os to storage as part of storage calibration. There is one slave process per CPU on each node of the database.
Yes
Yes
No
CTWR
Change Tracking Writer Process
Tracks changed data blocks as part of the Recovery Manager block change tracking feature
No
No
No
DBRM
Database Resource Manager Process
Sets resource plans and performs other Resource Manager tasks.
No
Yes
No
DBW 0..j
Database Writer Process
Writes modified blocks from the database buffer cache to the data files. There can be 1 to 100 Database Writer Processes. The names of the first 36 Database Writer Processes are DBW0-DBW9 and DBWa-DBWz. The names of the 37th through 100th Database Writer Processes are BW36-BW99.
Yes
Yes
No
DIA0
Diagnostic Process 0 (although 10 possible, only 0 is currently used)
Responsible for hang detection and deadlock resolution. Triggers DIAG to perform diagnostic tasks.
Yes
Yes
No
DIAG
Diagnostic Capture Process
Performs diagnostic dumps and executes global oradebug commands.
Yes
Yes
No
DMnn
Data Pump Master Process
Coordinates the Data Pump job tasks performed by Data Pump worker processes and handles client interactions.
No
No
No
Dnnn
Dispatcher Process
In a Shared Server configuration, dispatchers place connection requests in a connection request queue.
No
Yes
No
DWnn
Data Pump Worker Process
Performs Data Pump tasks as assigned by the Data Pump Master Process.
No
No
No
EMNC
EMON Coordinator Process
Coordinates the event management and notification activity in the database, including Streams Event Notifications, Continuous Query Notifications, and Fast Application Notifications. Spawns Ennn processes.
No
No
No
Ennn
EMON Slave Process
Performs database event management and notifications.
No
No
No
FBDA
Flashback Data Archiver Process
Archives historical rows for tracked tables into flashback data archives and manages archive space, organization, and retention
No
No
No
FMON
File Mapping Monitor Process
Spawns FMPUTL, an external non-Oracle Database process that communicates with the mapping libraries provided by storage vendors. Responsible for managing the mapping information.
No
No
No
GEN0
General Task Execution Process
Performs required tasks including SQL and DML.
Yes
Yes
No
Innn
Disk and Tape I/O Slave Process
Serves as an I/O slave process spawned on behalf of DBWR, LGWR, or an RMAN backup session.
No
No
No
Jnnn
Job Queue Slave Processes
Processes jobs in the queue. Spawned by CJQ0.
No
Yes
No
LGn
Log Writer Slave
On multiprocessor systems, LGWR creates slave processes to improve the performance of writing to the redo log. LGWR slaves are not used when there is a SYNC standby destination.
No
No
Yes
LGWR
Log Writer Process
Writes the log buffer out to the redo logs.
Yes
Yes
No
Lnnn
Pooled Server Process
Handles client requests in Database Resident Connection Pooling.
No
No
No
LREG
Listener Registration Process
LREG notifies the listeners about instances, services, handlers, and endpoint.
Yes
Yes
Yes
MMAN
Memory Manager Process
Serves as the SGA Memory Broker and coordinates the sizing of the memory components.
No
Yes
No
MMNL
Manageability Monitor Lite Process
Performs frequent and lightweight manageability-related tasks, such as session history capture and metrics computation.
No
Yes
No
MMON
Manageability Monitor Process
Collects statistics for the Automatic Workload Repository.
No
Yes
No
Mnnn
MMON Slave Process
Performs manageability tasks on behalf of MMON.
No
No
No
MSnn
LogMiner Worker Process
Reads redo log files and translates and assembles into transactions.
No
No
No
Nnnn
Connection Broker Process
Monitors idle connections and hands off active connections in Database Resident Connection Pooling
No
No
No
OFSD
Oracle File Server Background Process
This background process listens for new file system requests, both management (like mount, unmount, and export) and I/O requests, and executes them using Oracle threads.
Yes
Yes
No
PMON
Process Monitor
Recovers failed process resources. If Shared Server architecture is used, PMON monitors and restarts any failed dispatcher or server processes.
Yes
Yes
No
Pnnn
Parallel Query Slave Process
Started and stopped as needed to participate in parallel query operations.
No
No
No
PRnn
Parallel Recovery Process
Performs tasks assigned by the coordinator process performing parallel recovery
No
No
No
PSP0
Process Spawner Process
Starts and stops Oracle processes. Reduces workload of RBAL by starting / stopping ASM rebalance slaves.
No
Yes
No
RCBG
Result Cache Background Process
Supports SQL query and PL/SQL function result caches.
No
No
No
RECO
Recoverer Process
Resolves failures involving distributed transactions.
No
Yes
No
RM
RAT Masking Slave Process
This background process is used with Data Masking and Real Application Testing.
No
Yes
Yes
RPnn
Capture Processing Worker Process
Processes a set of workload capture files.
No
No
No
RPOP
Instant Recovery Repopulation Daemon
Responsible for re-creating and/or repopulating data files from snapshot files and backup files. The RPOP process is responsible for re-creating and repopulating data files from snapshots files. It works with the instant recovery feature to ensure immediate data file access. The local instance has immediate access to the remote snapshot file's data, while repopulation of the recovered primary data files happens concurrently. Any changes in the data are managed between the instance's DBW processes and RPOP to ensure the latest copy of the data is returned to the user.
No
No
Yes
RVWR
Recovery Writer Process
Writes flashback data to flashback database logs in the flash recovery area.
No
No
No
SAnn
SG Allocator
A small fraction of SGA is allocated during instance startup. The SAnn process allocates the rest of SGA in small chunks. The process exits upon completion of SGA allocation.
No
Yes
Yes
SMCO
Space Management Coordinator Process
Coordinates the execution of various space management related tasks, such as proactive space allocation and space reclamation.
No
Yes
No
SMON
System Monitor Process
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 management
Yes
Yes
No
Snnn
Shared Server Process
In a Shared Server configuration, shared servers check a connection request queue (populated by dispatchers) and services the connection requests.
No
Yes
No
VKRM
Virtual Scheduler for Resource Manager Process
Serves as centralized scheduler for Resource Manager activity.
No
Yes
No
VKTM
Virtual Keeper of Time Process
Responsible for providing a wall-clock time (updated every second) and reference-time counter (updated every 20ms and available only when running at elevated priority).
Yes
Yes
No
Wnnn
Space Management Slave Process
These are slave processes spawned by SMCO to execute space management tasks.
No
Yes
No

which process starts first when instance is started?

The first process that will be started when we start instance is PSP process. This is called PROCESS SPAWNER.  This process is introduced in 10g and is responsible for creating and managing other oracle backgroung processes.
As the name specifies, this process can spawn so that you will see the process name as PSP0 in alert log file.