Home > Workload Solutions > Oracle > White Papers > Dell PowerMax 2500 and 8500 Best Practices for Mission Critical Oracle Databases > Service Levels overview
PowerMax can maintain high performance at scale, often with many databases and applications consolidated into one storage system. To help with performance management based on business priorities, PowerMax manages the I/O latencies of the SGs based on their Service Levels (SL).
When selecting None SL, the PowerMax storage system assigns a SL called Optimized to the SG. This SL receives the best performance that the system can provide but has the lowest priority in comparison with other SLs. Also, between SGs sharing the same Optimized SL, it is possible that increased activity of one SG will affect the performance of another SG. This is because all SGs share the same system priorities and performance goals. Using specific SLs can prevent this situation.
Use cases for SLs include caging the performance of less important applications (“noisy neighbor”) and prioritizing production compared to test/dev systems. This also satisfies the needs of service providers or organizations using chargeback, which allows their clients to pay for a service level.
When using SLs, critical systems can be assigned a SL such as Diamond, Platinum, or Gold to ensure that their performance goals have a higher priority over applications with a lower SL such as Silver, Bronze, or Optimized.
The following figure lists the SL prioritizations and their associated performance target goals:
When an SG with a SL of higher priority struggles to maintain its performance target goal, it can cause SGs with lower priority SLs to slow down (increase their I/O latency) so it can maintain its higher priority performance goals. For example, Diamond SGs can affect Platinum SGs, which can affect Gold SGs. Any SG with a higher priority (a non-Optimized SL) can affect optimized SGs.