Shared Database Servers
- by shivanshu.upadhyay
As more enterprises consolidate their database environments to support private cloud initiatives, ISVs will have to deal with sceanrios where they need to run on a shared powerful database server like Exadata. Some ISVs are concerned about meeting SLAs for performance in a shared environment. Outside the virtualization world, there are capabilities of Oracle Database which can be used to prevent resource contention and guarantee SLA. These capabilities are -
1) Instance Caging - This guarantees the CPU allocated or limits the maximum number of CPUs (and so the number of Oracle processes) that an instance of Database can use simultaneously. With this feature, ISVs can be assured that their application is allocated adequate CPUs even if the database server is shared with other applications.
2) CPU Resource Allocation with Database Resource Manager - This allocates percentages of CPU time to different users and applications within a database. ISVs can use this feature to ensure that priority user or workloads within their application get CPU resources over other requirements.
3) Exadata I/O Resource Manager - The Database Resource Manager feature in Oracle Database 11g has been enhanced for use with Exadata. This allows the sharing of storage between databases without fear of one database monopolizing the I/O bandwidth and impacting the performance of the other databases sharing the storage. This can be used to ensure that I/O does not become a performance bottleneck due to poor design of other applications sharing the same server.
