What is Oracle LREG?
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What is Oracle LREG?
LREG (Listener Registration) is an Oracle background process created when you start an Oracle 12c or higher database instance. This function was handled by the PMON process in earlier releases.It registers the instance with the listeners.
What is ARCn process?
The archiver process (ARCn) copies redo log files to a designated storage device after a log switch has occurred. ARCn processes are present only when the database is in ARCHIVELOG mode, and automatic archiving is enabled. An Oracle instance can have up to 10 ARCn processes (ARC0 to ARC9).
What are the background processes involved in data guard?
In this post let us understand the Oracle dataguard Architecture and processes with the help of diagrams. LNS process of primary database captures redo from redo log buffer. Send it to RFS process of standby database through oracle net. RFS process then writes that redo information to standby redo log files.
What is Ckpt process in Oracle?
The CKPT process, which always exists in Oracle8 but is optional in Oracle7, is responsible for updating the headers of all Oracle datafiles at the time of a checkpoint. In Oracle7, this task may be performed by the LGWR process, but if there are many datafiles in the database then LGWR performance may be reduced.
What is Oracle process Architecture?
A client process runs the application or Oracle tool code. An Oracle process is a unit of execution that runs the Oracle database code. In the multithreaded architecture, an Oracle process can be an operating system process or a thread within an operating system process.
What is ARCn process why it is important?
ARCn is an oracle background process responsible for copying the entirely filled online redo log file to the archive log. Once these files have been copied, they can be overwritten. The n in ARCn represents the sequence number of the archiver process.
How do I check ASM background process?
- ASMB – ASM Background Process.
- RBAL – ASM Rebalance Master Process.
- ARBn – ASM Rebalance Process.
- DBWR – Database Writer Process.
- SMON – System Monitor Process.
- CKPT – Checkpoint Process.
- PSP0 – Process Spawner Process.
- GMON – ASM Disk Group Monitor Process.
What is the difference between user process and server process in Oracle?
In this configuration, a user process runs the database application on one machine, and a server process runs the associated Oracle server on another machine.
How many Lgwr processes are there in Oracle 12c?
While there is always only one LGWR for an Oracle instance, Oracle allows busy DML databases to spawn multiple log writer factotum processes (multiple LGWR slave processes that are owned and governed by the master LGWR).
What is MRP process in Data Guard?
The Managed Recovery Process (MRP) actually does the work of maintaining and applying the archived redo logs. Role Management Services – Control the changing of database roles from primary to standby. The services include switchover, switchback and failover.
What is M000 background process in Oracle?
M000 background process generates a trace file at database startup, related to PGA sizing. The trace file contains information related to process memory, similar to the following: Note the allocation of 384MB for qesmmCheckPgaL in the above.
What is fuzzy in V Datafile_header?
Consistency – The “fuzzy”: column will always read “NO” unless the data file is not consistent, then the fuzzy column will read ‘YES’. An inconsistent file in v$datafile_header indicates a file in need of recovery (roll-forward).
What is Wal segment?
A WAL segment is a 16 MB file, by default, and it is internally divided into pages of 8192 bytes (8 KB). The first page has a header-data defined by the structure XLogLongPageHeaderData, while the headings of all other pages have the page information defined by the structure XLogPageHeaderData.
Which is the best way to distribute Oracle Database processes?
In general, it is better to be connected through a dispatcher and use a shared server process. This is illustrated in Figure 4-2, “Oracle Database Shared Server Processes”. A shared server process can be more efficient because it keeps the number of processes required for the running instance low.
