6 Documentation Addendum

This section contains corrections to the following Oracle Documentation:

Section 6.1, "Oracle Automatic Storage Management Administrator's Guide"

Section 6.2, "Oracle Clusterware Administration and Deployment Guide"

6.1 Oracle Automatic Storage Management Administrator's Guide

Note the following changes with regard to the Oracle Automatic Storage Management Administrator's Guide, 11g Release 2 (11.2), part number E18951.

6.1.1 Chapter 1: Introduction to Oracle Automatic Storage Management

In the section "Extents" found in the section titled "About Oracle ASM Files" under the main section titled "Understanding Oracle ASM Concepts" should read as follows:

The contents of Oracle ASM files are stored in a disk group as a set, or collection, of extents that are stored on individual disks within disk groups. Each extent resides on an individual disk. Extents consist of one or more allocation units (AU). To accommodate increasingly larger files, Oracle ASM uses variable size extents.

Variable size extents enable support for larger Oracle ASM data files, reduce SGA memory requirements for very large databases, and improve performance for file create and open operations. The initial extent size equals the disk group allocation unit size and it increases by a factor of 4 or 16 at predefined thresholds. This feature is automatic for newly created and resized data files when specific disk group compatibility attributes are set to 11.1 or higher. For information about compatibility attributes, see "Disk Group Compatibility".

For disk groups with an AU size less than 4 MB, the extent size of a file varies as follows:

  • Extent size always equals the disk group AU size for the first 20000 extent sets (0 - 19999).

  • Extent size equals 4*AU size for the next 20000 extent sets (20000 - 39999).

  • Extent size equals 16*AU size for the next 20000 and higher extent sets (40000+).

Figure 1-4 shows the Oracle ASM file extent relationship with allocation units ...

For disk groups with AU sizes greater than or equal to 4 MB, the extent size of a file, depending on the redundancy of the disk group, varies as follows:

  • For the 4 MB AU size, the extent size equals the disk group AU size for the first 15658728, 6710880, and 3728269 extents for external, normal, and high redundancy disk groups respectively.

  • For the 8 MB AU size, the extent size equals the disk group AU size for the first 16777216, 7829368, and 4846749 extents for external, normal, and high redundancy disk groups respectively.

  • For the 16 MB AU size, the extent size equals the disk group AU size for the first 16777216, 8388608, and 5405989 extents for external, normal, and high redundancy disk groups respectively.

  • For the 32 MB AU size, the extent size equals the disk group AU size for the first 16777216, 8388608, and 5592405 extents for external, normal, and high redundancy disk groups respectively.

For all cases, the size of the remaining extent sets is 16*AU size. Extents with a size equal to 4*AU size are not created.

6.1.2 Chapter 3: Administering Oracle ASM Instances

In the PROCESSES description found in the section titled "Oracle ASM Parameter Setting Recommendations" under the section titled "Configuring Initialization Parameters for Oracle ASM Instances," the following paragraph should be included:

For Oracle Grid Infrastructure, 11g Release 2 (11.2.0.3 and 11.2.0.4), the PROCESSES initialization parameter defaults to a value equal to "available CPU cores * 80 + 40" in the Oracle ASM SPFILE. Because the default value for the MEMORY_TARGET initialization parameter is based on the value of PROCESSES, the value can be insufficient if there is a large number of CPU cores or a large number of disk groups. You should increase the value of the MEMORY_MAX_TARGET and MEMORY_TARGET initialization parameters before upgrading to or installing Oracle Grid Infrastructure, 11g Release 2 (11.2.0.3 and 11.2.0.4).

6.1.3 Chapter 4: Administering Oracle ASM Disk Groups

In the STORAGE.TYPE description found in the section titled "Disk Group Attributes," the restriction that "ZFS storage must be added through Direct NFS (dNFS)" no longer applies if the COMPATIBLE.ASM and COMPATIBLE.RDBMS disk group attributes are set to 11.2.0.4 or higher

6.1.4 Chapter 12: Oracle ASM Command-Line Utility

Note the following changes with regard to Chapter 12 of the Oracle Automatic Storage Management Administrator's Guide, 11g Release 2 (11.2), part number E18951.

6.1.4.1 Section: ASMCMD Volume Management Commands

In the section "volcreate" found in the "ASMCMD Volume Management Commands" section, the following warning applies:

WARNING:

Specifying --redundancy unprotected means that Oracle ASM mirroring is not available for data recovery with the Oracle ADVM volume. The redundancy setting (normal) of the disk group does not provide mirroring for an unprotected Oracle ADVM volume. The unprotected configuration is not recommended for production environments as intermittent storage access failures can result in the loss of data. Backups are strongly recommended.

6.1.4.2 Section: ASMCMD Disk Group Management Commands

In the section "iostat" of the "ASMCMD Disk Group Management Commands" section, the units for the I/O times specified by the Read_Time and Write_Time attributes should be seconds, not hundredths of seconds.

6.2 Oracle Clusterware Administration and Deployment Guide

Note the following changes with regard to the Oracle Clusterware Administration and Deployment Guide for 11g Release 2 (11.2), part number E41959.

6.2.1 Chapter 5: Cloning Oracle Clusterware

In the section titled "Creating a Cluster by Cloning Oracle Clusterware," "Step 2: Deploy the Oracle Grid Infrastructure Home on the Destination Nodes" incorrectly instructs you to run the following commands to restore the cleared information:

chmod u+s Grid_home/bin/oracle 
chmod g+s Grid_home/bin/oracle 
chmod u+s Grid_home/bin/extjob 
chmod u+s Grid_home/bin/jssu 
chmod u+s Grid_home/bin/oradism

These instructions should be ignored. The Oracle Clusterware Administration and Deployment Guide is fixed in 12c Release 1 (12.1) and higher releases.