Directory Server quickly calculates the number of pending replication changes. Directory Server finds the oldest change that the consumer is aware of and can compare it with the other servers, making it possible to calculate the replication delay. From this change, the consumer can also browse the list of changes until the most recent change, and count the number of changes that need to be applied.
Moreover, this attribute can be queried with virtually no impact to Directory Server performance, regardless of how large the change log grows.
In the Directory Service Control Center, you can view a summary of all the pending changes for a given suffix. In the Suffixes tab, the pending changes are in the Missing Changes column, as shown in the following figure.