Chapter 8. Tuning the Replication Performance

8.1. Improving the Multi-supplier Replication Efficiency

The replication latency in a multi-supplier replication environment, especially if the servers are connected using a wide area network (WAN), can be high in case of multiple suppliers are receiving updates at the same time. This happens when one suppliers exclusively accesses a replica without releasing it for a long time. In such situations, other suppliers cannot send updates to this consumer, which increases the replication latency.
To release a replica after a fixed amount of time, set the nsds5ReplicaReleaseTimeout parameter on replication suppliers and hubs.

Note

The 60 seconds default value is ideal for most environments. A value set too high or too low can have a negative impact on the replication performance. If the value is set too low, replication servers are constantly reacquiring one another, and servers are not able to send many updates. In a high-traffic replication environment, a longer timeout can improve situations where one supplier exclusively accesses a replica. However, in most cases, a value higher than 120 seconds slows down replication.

8.1.1. Setting the Replication Release Timeout Using the Command Line

To set the replication release timeout using the command line:
  1. Set the timeout value: 
    # dsconf -D "cn=Directory Manager" ldap://supplier.example.com replication set --suffix="dc=example,dc=com" --repl-release-timeout=70
    This command sets the replication release timeout value for the dc=example,dc=com suffix to 70 seconds.
  2. Restart the Directory Server instance: 
    # dsctl instance_name restart

8.1.2. Setting the Replication Release Timeout Using the Web Console

To set the replication release timeout using the Web Console:
  1. Open the Directory Server user interface in the web console. For details, see Logging Into Directory Server Using the Web Console section in the Red Hat Directory Server Administration Guide.
  2. Select the instance.
  3. Open the Replication menu, and select Configuration.
  4. Click Show Advanced Settings.
  5. Set the timeout value in the Replication Release Timeout field.
  6. Click Save.
  7. Click the Actions button, and select Restart Instance.