This preface contains:
The following are changes in Oracle Real Application Clusters Administration and Deployment Guide for Oracle Real Application Clusters (Oracle RAC) 12c:
Changes in Oracle Real Application Clusters 12c Release 1 (12.1.0.2)
Changes in Oracle Real Application Clusters 12c Release 1 (12.1.0.1)
The following features are new in this release:
In-Memory Column Store
The In-Memory Column Store is an optional area in the SGA that stores whole tables, table partitions, and individual columns in a compressed columnar format. The database uses special techniques, including SIMD vector processing, to scan columnar data extremely rapidly. The In-Memory Column Store is a supplement to, rather than a replacement for, the database buffer cache.
See Also:
Oracle Database Data Warehousing Guide for more informationIn-Memory Transaction Manager
The In-Memory Transaction Manager is an independent engine that automatically provides read consistency for transactions that apply changes to the In-Memory Column Store. This engine is necessary because tables and partitions residing in the In-Memory Column Store are stored in columnar format in memory and in row-major format in the data files and database buffer cache.
See Also:
Oracle Database Concepts for more informationRapid Home Provisioning
Rapid Home Provisioning enables you to deploy Oracle homes based on images stored in a catalog of precreated software homes.
See Also:
Oracle Clusterware Administration and Deployment Guide for more informationFull Database In-Memory Caching
In this release you can cache an entire database in memory. Use this feature when the buffer cache size of each instance is greater than the size of the whole database. In Oracle RAC systems, for well-partitioned applications, you can use this feature when the combined buffer caches of all database instances (with some extra space to handle duplicate cached blocks between instances) is greater than the database size.
See Also:
Oracle Database Performance Tuning Guide for more informationMemory Guard Does Not Require Oracle Database QoS Management to be Active
With this release, Memory Guard is enabled by default independent of whether you use Oracle Database Quality of Service Management (Oracle Database QoS Management). Memory Guard detects memory stress on a node and causes new sessions to be directed to other instances until the existing workload drains and frees memory. When free memory increases on the node, then services are enabled again to automatically accept new connections.
The following features are new in this release:
Application Continuity
Before this release, application developers were required to deal explicitly with outages of the underlying software, hardware, and communications layers if they wanted to mask outages from end users.
In Oracle Database 10g, Fast Application Notification (FAN) quickly delivered exception conditions to applications. However, neither FAN nor earlier Oracle technology reported the outcome of the last transaction to the application, or recovered the in-progress request from an application perspective. As a result, outages were exposed leading to user inconvenience and lost revenue. Users could unintentionally make duplicate purchases and submit multiple payments for the same invoice. In the problematic cases, the administrator needed to reboot the mid-tier to deal with the incoming problems this caused.
Application Continuity is an application-independent feature that attempts to recover incomplete requests from an application perspective and masks many system, communication, hardware failures, and storage outages from the end user.
See Also:
Oracle Database Concepts for more information
Transaction Guard for Java
This feature exposes the new Application Continuity infrastructure to Java. It provides support for:
At-most-once transaction execution protocol, such as transaction idempotence
API for retrieving logical transaction ID (LTXID)
Attribute to get Connection or Session status
See Also:
Oracle Database JDBC Developer's Guide for more informationTransaction Idempotence
This feature delivers a general purpose, application-independent infrastructure that enables recovery of work from an application perspective and masks most system, communication, and hardware failures from the user. Transaction idempotence ensures that your transactions are executed on time and, at most, once.
See Also:
Oracle Database Development Guide for more informationOracle Flex Clusters
Large clusters consisting of, potentially, thousands of nodes, provide a platform for Oracle RAC to support massive parallel query operations.
See Also:
Oracle Clusterware Administration and Deployment Guide for more information about Oracle Flex ClustersShared Oracle ASM Password File in a Disk Group
This feature implements the infrastructure needed to address the bootstrapping issues of storing an Oracle Automatic Storage Management (Oracle ASM) shared password file in an Oracle ASM disk group.
Global Data Services
Similar to the way Oracle RAC supports a database service and enables service-level workload management across database instances in a cluster, Global Data Services provides Oracle RAC-like connect-time and run-time load balancing, failover, and centralized service management for a set of replicated databases that offer common services. The set of databases can include Oracle RAC and nonclustered Oracle databases interconnected with Oracle Data Guard, Oracle GoldenGate, or any other replication technology.
See Also:
Oracle Database Global Data Services Concepts and Administration Guide for more informationShared Grid Naming Service
One instance of Grid Naming Service (GNS) can service any number of clusters.
See Also:
Oracle Clusterware Administration and Deployment Guide for more informationWhat-If Command Evaluation for Oracle RAC
This feature of Oracle Clusterware improves resource management and availability, through a mechanism that provides a policy response to a hypothetical planned or unplanned event, without modifying the state of the system.
In Oracle RAC, enhancements to SRVCTL aid you in determining the impact of certain commands before you run them to determine the potential impact of the command.
See Also:
"SRVCTL Usage Information" for a list of SRVCTL commands with What-If functionality
Oracle Clusterware Administration and Deployment Guide for a list of Oracle Clusterware Control (CRSCTL) utility commands with similar enhancements
Restricting Service Registration for Oracle RAC Deployments
This feature allows listener registration only from local IPs by default and provides the ability to configure and dynamically update a set of IP addresses or subnets from which registration requests are allowed by the listener.
See Also:
Oracle Database Net Services Administrator's Guide for more informationRestricting Service Registration with Valid Node Checking
This feature enables the network administrator to specify a list of nodes and subnet information from which the Single Client Access Name (SCAN) listener accepts registration. You can specify the nodes and subnets information using SRVCTL, and SRVCTL stores the information in the SCAN listener resource profile and this information is also written to the listener.ora file. Restricting client access to a database makes Oracle RAC even more secure and less vulnerable to security threads and attacks.
Pluggable Databases
Pluggable Databases enables an Oracle database to contain a portable collection of schemas, schema objects, and nonschema objects that appears to an Oracle Net client as a separate database. This self-contained collection is called a pluggable database (PDB). A container database (CDB) is an Oracle database that includes zero, one, or many user-created pluggable databases (PDBs). You can unplug a PDB from a CDB and plug it into a different CDB.
See Also:
Oracle Database Administrator's GuideSupport of Oracle Home User on Windows
Starting with Oracle Database 12c, Oracle Database supports the use of an Oracle home user, which you can specify at installation time. The Oracle home user is associated with a Windows domain user. The Windows domain user should be a low-privileged (non-Administrator) account to ensure that the Oracle home user has a limited set of privileges, thus ensuring that the Oracle Database services have only those privileges required to run Oracle products.
Windows Administrator user privileges are still required to perform Oracle software maintenance tasks including installation, upgrade, patching, and so on. Oracle Database administrative tools have been enhanced to ask for the password of the Oracle home user, if needed. In Oracle RAC environments, you can store the password for the Oracle home user in a secure wallet. If such a wallet exists, then the Oracle Database administrative tools automatically use the password from the wallet and do not require the user to enter the password for the Oracle home user.
Cluster Resources for Oracle ACFS and Oracle ADVM
Oracle Clusterware resource support includes enhancements for Oracle homes stored on Oracle Automatic Storage Management Cluster File System (Oracle ACFS), Oracle ACFS General Purpose file systems for Grid homes, and Oracle ASM Dynamic Volume Manager (Oracle ADVM) volumes. These resources, that Oracle Clusterware manages, support automatic loading of Oracle ACFS, Oracle ADVM and OKS drivers, disk group mounts, dynamic volume enablement, and automatic Oracle ACFS file system mounts.
See Also:
Oracle Automatic Storage Management Administrator's Guide for more informationOracle Highly Available NFS
You can configure Oracle ACFS as a highly available, exported file system service. This service uses Oracle ACFS' clusterwide data consistency and coherency, in combination with virtual IP addresses, to provide failover capability for NFS exports. By mounting the NFS export from this virtual IP address, a client can be assured that, if one node of the cluster is available, then the NFS export will be available.
See Also:
Oracle Automatic Storage Management Administrator's Guide for more informationPolicy-Based Cluster Management and Administration
Oracle Grid Infrastructure allows running multiple applications in one cluster. Using a policy-based approach, the workload introduced by these applications can be allocated across the cluster using a policy. In addition, a policy set enables different policies to be applied to the cluster over time as required. You can define policy sets using a web-based interface or a command-line interface.
Hosting various workloads in the same cluster helps to consolidate the workloads into a shared infrastructure that provides high availability and scalability. Using a centralized policy-based approach allows for dynamic resource reallocation and prioritization as the demand changes.
See Also:
Oracle Clusterware Administration and Deployment Guide for more informationOnline Resource Attribute Modification
Oracle Clusterware manages hardware and software components for high availability using a resource model. You use resource attributes to define how Oracle Clusterware manages those resources. You can modify certain resource attributes and implement those changes without having to restart the resource using online resource attribute modification. You manage online resource attribute modification with certain SRVCTL and CRSCTL commands.
Deprecation of single-letter SRVCTL CLI options
All SRVCTL commands have been enhanced to accept full-word options instead of the single-letter options. All new SRVCTL command options added in this release support full-word options, only, and do not have single-letter equivalents. The use of single-letter options with SRVCTL commands might be desupported in a future release.
Deprecation of Oracle Restart
Oracle Restart is deprecated in Oracle Database 12c. Oracle Restart is currently restricted to manage single-instance Oracle databases and Oracle ASM instances only, and is subject to desupport in future releases. Oracle continues to provide Oracle ASM as part of the Oracle Grid Infrastructure installation for Standalone and Cluster deployments.
See Also:
Oracle Database Upgrade Guide for more informationOracle Cluster File System for Windows
Oracle no longer supports Oracle Cluster File System (OCFS) on Windows.
Raw (block) storage devices for Oracle Database and related technologies
Oracle Database 12c release 1 (12.1) and its related grid technologies, such as Oracle Clusterware, no longer support the direct use of raw or block storage devices. You must move existing files from raw or block devices to Oracle ASM before you upgrade to Oracle Clusterware 12c release 1 (12.1).