The following are some common use cases for Oracle Global Data Services:
Ensuring Business Continuity with Automated Database Failover
Global Data Services extends Oracle RAC-style service failover (within and across data centers) and management capabilities to replicated databases, and takes into account service placement policies. It achieves higher availability and improved manageability by enabling Global Data Services with Active Data Guard and Oracle GoldenGate.
If a database global service crash occurs, GDS, considering the service placement attributes, automatically performs an inter-database service failover to another available database in the pool. GDS sends Fast Application Notification (FAN) events so that the client connection pools can reconnect to the new database where the global service has been started.
Minimizing Resource Requirement with Intelligent Load Balancing
Global Data Services extends Oracle RAC-style connect-time and run-time load balancing capabilities (within and across data centers) to a set of replicated databases. The algorithm takes into account load metrics, region affinity, network latency, and load balancing goals. It maximizes performance and achieves efficient resource utilization by enabling Global Data Services on Active Data Guard and Oracle GoldenGate.
GDS enables runtime load balancing across replicated databases by publishing a real-time load balancing advisory for connection pool-based clients (for example, OCI, JDBC, ODP.NET, WebLogic, and so on.). The connection pool-based clients subscribe to this load-balancing advisory and route database requests in real time across already-established connections.
With GDS's runtime connection load balancing feature, application client work requests are dynamically routed to the database that offers the best performance. In addition, GDS also supports the ability to dynamically re-distribute connections when the database performance changes.
With GDS's connect time load balancing, global service managers use the load statistics from all databases in the GDS pool, inter-region network latency, and the configured connect-time load balancing goal to route the incoming connections to the best database in a GDS pool.
Geo-Aware Workload Routing for Faster Response Times
With GDS, you can choose to configure client connections to be routed among a set of replicated databases in a local region. This capability allows you to maximize application performance (avoiding the network latency overhead of accessing databases in remote areas).
Improving Read Performance with Smart Replication Lag Aware Routing
With Oracle Active Data Guard, standbys may lag behind the primary database. A global service allows you to choose the acceptable lag tolerance for a given application. GDS routes requests to a standby database whose lag is below the limit. If the lag exceeds the lag limit, the service is relocated to another available standby database that lags below the threshold. New requests are routed to a standby database that satisfies the lag limit. If no standbys meet the threshold, the workload is routed to the primary database. When the lag is resolved or comes within the limit, GDS automatically brings up the service.
With Oracle GoldenGate replication, when the lag exceeds the lag threshold defined for a service, that service is stopped on that database. The service is restarted if the lag comes back within the threshold. After the service has been stopped, the global service manager automatically performs failover processing. Any new connections to this service are directed elsewhere than the lagged database. So, if there are two databases in the pool, and the service is preferred_all with lag=10 initially, the service runs on both databases, and the connections are load-balanced. If the second database goes past the lag threshold, the service is stopped there, and any new connections are directed only to the first database. If the lag comes back within the threshold, the service is restarted, load balancing continues, and new connections can use the second database. If no replicas meet the threshold, the workload is routed to the primary database.
Boosting Query Speed with Ultra-Fast Cache
Oracle True Cache is an in-memory, consistent, and automatically managed SQL cache for Oracle Database. You can deploy Oracle True Cache with Oracle Database Global Data Services (GDS) to improve application response time and manage workload routing, dynamic load balancing, and service failover across multiple True Caches and other database replicas.