Flow control for remote standalone secondary servers

Flow control provides a way to limit log activity on the primary server so that remote standalone (RS) secondary servers in the cluster do not fall too far behind on processing transactions. Enabling flow control ensures that logs on RS secondary servers remain current if the servers are on a busy or intermittent network.

Set the RSS_FLOW_CONTROL configuration parameter on the primary server to enable flow control. All RS secondary servers in the cluster are affected by the primary server's RSS_FLOW_CONTROL configuration parameter setting. When flow control is active, users connected to the primary server may experience slower response time.

Logs are always sent to the RS secondary server in the order in which they were received.

To check if flow control is active for a RS secondary server, use the onstat -g rss verbose command, and compare the RSS flow control value to the Approximate Log Page Backlog value. If the Approximate Log Page Backlog is higher than the first value of RSS flow control, flow control is active. If the Approximate Log Page Backlog is lower than the second value of RSS flow control, flow control is disabled.


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