To ensure the system runs without performance issues, system administrators often size the system to handle peak workloads. This peak workload sizing guarantees that the system always has sufficient capacity, but it can be an expensive solution if peak workloads only occur for a few hours each month.
System load comes in three clearly recognizable variants:
- Normal workload is the workload that occurs on the system during normal operations.
- Recurring peak workload is workload that is caused by repeatedly scheduled tasks that run for example hourly, daily, weekly, monthly or any other period.
- Ad-hoc peak workload occurs at times where many (heavy) queries are executed simultaneously on the system.
A more cost-efficient method would be to add or remove an SAP HANA Cloud elastic compute node (ECN) based on the current workload state. ECNs provide elasticity in the SAP HANA Cloud database by offering additional temporary processing capacity as needed to handle workload peaks.
An ECN is an additional instance running a computeserver process (such as an indexserver). ECNs have only temporary persistence and can be easily added or removed based on the current workload state.
Note
Adding an ECN incurs additional costs while the computeserver is running, but it optimizes the total cost of ownership.Depending on your requirements and how you use the ECN, the implementation steps may involve the following functional areas of SAP HANA Cloud:
- Provisioning instances.
- Using workload classes to route queries to the ECN.
- Table replication.
- Table placement and table redistribution.
The administration tools in SAP HANA Cloud Central support the implementation and monitoring of elastic compute nodes. These tools include:
- An ECN sizing application.
- A cost estimator.
- A workload analyzer.
- A recommendations application to determine when to deploy ECNs.
The command line can be used for all activities as well. For developers, a REST API is available that provides features to provision, update, and deprovision an ECN, as well as retrieve details about the status of nodes currently in operation.
Summary
Implementing SAP HANA Cloud ECNs offers a cost-efficient solution to manage varying workloads. Instead of sizing the system for peak workloads, ECNs provide temporary processing capacity to handle normal, recurring peak, and ad-hoc peak workloads. ECNs can be easily added or removed based on current workload state, optimizing the total cost of ownership despite additional costs while running. Implementation involves several functional areas, including provisioning instances, using workload classes, table replication, and table placement. Administration tools in SAP HANA Cloud Central support ECN implementation and monitoring, and a REST API is available for developers.
Related Information
For more information about SAP HANA Cloud ECNs, see: