Oracle 11g new features: oracle11g background process Overview ____oracle
Source: Internet
Author: User
One. Comparison of oracle11g background process and 10GR2
We know that the background process of an Oracle database is typically named after the Ora_, and here's a look at the background processes in oracle11g, with a single node Oracle instance
Two. ORACLE11G the functionality of a new background process
The new many background processes are: ORA_DBRM_ORCL,ORA_DIA0_ORCL,ORA_PSP0_ORCL,ORA_SMCO_ORCL,ORA_VKTM_ORCL,ORA_W000_ORCL,
The functions of these background processes are as follows:
DBRM: The database resource management process (the DB Resource Manager process), which is responsible for setting up resource planning and other resource management tasks.
DIAG: The database diagnostics process, the diagnosibility process, responsible for maintaining and managing various dump files for diagnostics and executing oradebug commands.
DIA0: Another database diagnostics process that detects pending (hang) and deadlock handling in an Oracle database.
Psp0:process Spawner, for generating Oracle processes
Smco:space management Coordinator, which is responsible for the coordination and management of space management, is responsible for the implementation of space allocation and recovery.
wnnn, named w000,w001,w002 ..., dynamically generated by Smco to perform the related tasks mentioned above.
Vktm:virtual Keeper of time, which is used to provide Wall-clock, which is updated every second. The Reference-time counter, which is updated every 20 milliseconds, looks a bit like the function of a timer.
Three. oracle11g Other background processes introduced in the new
Let's take a look at some of the other processes introduced in oracle11g, because some of the features aren't used in my test library, such as ASM, so it's not in the PS-EF results.
Gmon: The relationship between the disks used to maintain the ASM disk group.
KATE: When ASM's disk is offline, the process is responsible for the ASM's metafile IO read and write.
Mark: If there is a missed write request to the ASM offline disk, the process marks the state of the ASM allocated unit as stale
FBDA: A process involving a new feature of Flashback-da ta-archive, the Flashback da Ta archiver proces. Used to archive historical data for the tracked tables. The FBDA process is responsible for saving the front image of the data to the Flashback archive area after the transaction commits on the??? The process is also responsible for flashback data archive space management, allocation, retention, tracking tracked transactions.
What is "tracked tables": Refers to a table that has the Flashback archive feature enabled.
Rmsn:the Oracle RAC Management processes performs management tasks for Oracle RAC, such as the creation of RAC-related resources and the addition of new instances in the cluster.
dskm:the slave DiskMon Process, which is responsible for exchanging IO fencing information between an Oracle instance, an ASM instance, and a disk management process. If you use sage storage, the process is also responsible for managing some of the information that the sage stores.
Four. Review the background process for Oracle 10GR2
Finally, review some of the background processes in Oracle 10GR2:
The queue monitor processes (QMNN) is an optional process used by Oracle Streams Advanced queuing to monitor Message Queuing. These two types of process errors do not cause an error in the entire instance.
Mmon:manageability Monitor, associated with the new features of oracle10g-diagnostics, is responsible for managing some background tasks, rather than collecting statistics on recently modified SQL objects
MMNL: In relation to the new features of oracle10g-diagnostics, the output from the SGA will be refreshed to the database table according to the schedule, such as the historical information of the session.
Mman: Associated with the new features of oracle10g-diagnostics, responsible for performing some database internal tasks, automatically setting the SGA Size feature will use this process.
Rbal:rebalance. The process is responsible for coordinating the load balancing work between disk groups, running in a database instance that uses ASM. When adding or removing disks to an ASM disk group, the Rbal is responsible for processing the rebalancing request. It enables multiple instances to simultaneously access an ASM disk (global Open). Ultimately, the load balancing of data extensions is actually performed by the ORBN process. You can run multiple ORBN processes in an instance, ORB0,ORB1, and so on.
ASMB: Responsible for communicating with the ASM instance when using the ASM Disk group, providing update statistics to the ASM instance
The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion;
products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the
content of the page makes you feel confusing, please write us an email, we will handle the problem
within 5 days after receiving your email.
If you find any instances of plagiarism from the community, please send an email to:
info-contact@alibabacloud.com
and provide relevant evidence. A staff member will contact you within 5 working days.
