What is RBAL in ASM?

What is RBAL in ASM?

RBAL – ASM Rebalance Master Process – Coordinates rebalance activity. – In an ASM instance, it coordinates rebalance activity for disk groups and performs a global open on ASM disks. – In database instances, it manages ASM disk groups.

What is ASM process?

ASMB – ASM Bridge: This process is used to provide information to and from the Cluster Synchronization Service (CSS) used by ASM to manage the disk resources. It is also used to update statistics and provide a heartbeat mechanism. CKPT The CKPT process manages cross-instance calls (in RAC).

Which task does the RBAL process perform?

Rebalance Master (RBAL): This process manages disk rebalancing tasks in an ASM based storage. ASM Rebalance (ARBn): This process actually performs disk rebalance activity in an ASM instance.

How does ASM instance communicate with database instance?

Any database instance that is using an ASM disk group will contain a background process called OSMB. The OSMB process is responsible for communicating with the ASM instance. The RBAL background process within a database instance, called RBAL just like in the ASM Instance, performs a global open on ASM disks.

What is RBAL?

RBAL performs the opening and closing of the disks in the disk groups on behalf of Oracle database. This RBAL is the same process as in ASM instance but it performs a different function.

What is rebalancing in Oracle ASM?

Dynamic Storage Configuration. ASM enables you to change the storage configuration without having to take the database offline. It automatically rebalances—redistributes file data evenly across all the disks of the disk group—after you add disks to or drop disks from a disk group.

What is Ckpt process in Oracle?

CKPT (Oracle Checkpoint Process) is an Oracle background process that timestamps all datafiles and control files to indicate that a checkpoint has occurred. The “DBWR checkpoints” statistic (v$sysstat) indicates the number of checkpoint requests completed.

What is J000 process in Oracle?

Oracle slave processes (J000 – J999) executes the scheduled jobs. The CJQ0 process will be keeping track of the schedule and starts slave processes so as to execute the scheduled jobs.

How do I mount an ASM instance?

Startup and shutdown the Oracle ASM instance

1. Set the default Oracle_home environment variable to grid home where ASM is installed. EXPORT ORACLE_HOME=/up1/grid/12.2.0/dbhome_1.
2. Connect with sqlplus. SQLPLUS / as sysasm.
3. Start up the Oracle ASM Instance. SQL> STARTUP.
4. Check the spfile location or otherwise set it with.

What is the advantage of ASM in Oracle?

ASM lowers the Oracle database storage total cost of ownership and increases storage utilization while improving performance and availability as compared with traditional file system and volume management solutions. With ASM, less effort is required for managing your database storage environment.

What is the use of library cache?

The Library Cache is a piece of memory within the SGA that Oracle uses in order to store SQL Statements. It is used to store shared SQL.

What is Archiver process in Oracle?

The ARCH process is used to copy the contents of an online log file to another location, typically a disk file, when that log file becomes full. Oracle uses the online log files in a “round robin” fashion—that is, when all available online log files become full, the first file is reused.

What does RBAL do in an ASM instance?

A second additional background process, called RBAL (just like in the ASM Instance) performs a global open on ASM disks. A global open means that more than one database instance can be accessing the ASM disks at a time.

What are the background processes in Oracle ASM?

The ASM RBAL background process coordinates and spawns one or more of these slave processes to recover aborted ASM transactional operations. These processes run only in the Oracle ASM instance. Possible processes are ARS0-ARS9.

How does ASMB work with Oracle Cluster Registry?

ASMB also runs with Oracle Cluster Registry on ASM. In an ASM instance, it coordinates rebalance activity for disk groups and performs a global open on ASM disks. In a database instances, it manages ASM disk groups.

How does the Oracle ASM rebalance operation work?

Any change in the storage configuration like disk addition or dropping will trigger a oracle ASM rebalance operation The main objective of the oracle ASM rebalance operation is to always provide an even distribution of file extents and space usage across all disks in the diskgroup. Rebalancing is performed on all database files on a per file basis.