Best Practice 13.4 – Choose location to minimize latency

Deploy your SAP instances in Regions and Availability Zones that minimize latency for key business processes impacting end users, critical interfaces, and intra-system traffic.

Suggestion 13.4.1 – Select Region and cloud connectivity to optimize performance

Choose a Region based on proximity to your SAP end users and corporate data center. Select and size any cloud connectivity options (such as AWS Direct Connect and VPN) to accommodate your data transfer requirements.

Use SAP performance tools to understand the breakdown of user response time (such as network, GUI, application, and database) and evaluate the impact of any changes to the network round trip time as a result of increased latency. We recommend you focus on high frequency, low latency interfaces between systems in different locations.

If increased latency impacts certain end user groups, consider the use of end user compute services and accelerators.

Suggestion 13.4.2 – Be aware of SAP guidelines for intra-system latency

SAP provides guidance for acceptable network latency for two traffic patterns: between SAP application servers and the database, and between SAP HANA database servers (primary and secondary) for the purposes of data replication. AWS regional networks generally meet or exceed these requirements.

Network Latency between SAP application servers and database (Pattern 1)

The following SAP guidance for database to application server connectivity is based on systems running in a single data center, which does not reflect the resiliency benefits of a Multi-AZ deployment. An Availability Zone is one or more discrete data centers with redundant power, networking, and connectivity in an AWS Region separated by a meaningful distance (at least 10km).

Resilient SAP architectures in AWS typically involve deploying infrastructure across multiple AZs, including SAP application server and database instances.

If you have SAP transactions or batch jobs with time-critical performance requirements and that make a significant number of database calls, we recommend that you run these jobs on SAP application servers located in the same AZ as the database. This can be achieved by using SAP Logon Groups (transaction SMLG) for end users and a batch server group (transaction SM61) for background processing jobs. This helps ensure that the latency sensitive parts of the SAP workload run on application servers with the lowest latency to the database. Use tools such as NIPING to measure latency.

Network Latency between SAP HANA primary and secondary servers (Pattern 2)

The network latency between the primary and secondary instances will be a factor in the redo log shipping wait time. For synchronous replication, SAP recommends that this wait time should be in the low single millisecond range. This requirement can be achieved across AWS Availability Zones. Use tools such as NIPING to measure latency.

Suggestion 13.4.3 – Use placement groups for SAP HANA scale out

To meet the SAP certification for internode communication in an SAP HANA scale-out deployment, it is necessary to use a cluster placement group.