how it works
- If you log on using a logon group, the logon is automatically performed using the instance of the group that currently has the best dialog quality. This quality is a key figure that is calculated from the number of users logged on and the average dialog response time.
- To allow the different prerequisites of different instance to be taken into account in this calculation, you can set threshold values for the dialog response time and the number of users yourself. The larger the actual values for response time and the number of users are in comparison to the threshold values set, the lower the quality. These figures apply for the selected instance.
- The values for Response Time and Users are not absolute limits, but rather thresholds. Even if the current value for response time or number of users is higher than this threshold value, it is possible to log on to another instance. The threshold values only influence the calculation of the current logon server of the logon groups.
- You can use a preview to see how the settings of the threshold values can affect the quality calculation, based on the current performance data. Choose test to do this. In a logon group, the instance with the highest quality key figure is always selected for the logon.
- Choose Copy, and save your changes.
from:
http://sap.knowledgehills.com/Logon-Load-Balancing-in-SAP-R-3-Logon-Groups-SMLG-and-CCMS-Configuration-for-Basis-Admins/a21p1
