Dangers of Disabling Merges
MarkLogic Server is designed to periodically merge. It is dangerous to leave merges disabled on a database when there are any updates occurring to the system. While disabling merges might eliminate some contention for resources during periods where merges and other requests are simultaneously occurring on the system, the performance of MarkLogic Server will degrade over time if merges are not allowed to proceed when changes (inserts, updates, deletes) are made to the database.
Furthermore, disabling or eliminating merging may eventually lead to a condition in which the server is unable to make changes to the database. For example, when an in-memory stands fills up, it is written to an on-disk stand. MarkLogic Server has a fixed limit for the maximum number of stands (64), and eventually, that limit will occur and you will no longer be able to update your system. Therefore, there is no control available to disable merges. If you feel you need to disable merges and you have an active maintenance contract, you can contact MarkLogic Technical Support for help.
In most cases where merges are causing disruptions to your system, you should be able to adjust the merge policy parameters to settings that will work in your environment. If you feel you need to disable merges and you have an active maintenance contract, you can contact MarkLogic Technical Support for help. Monitor the system and make sure the number of stands per forest does not grow too high. For details on setting merge controls, see Configuring the Merge Policy and Configuring Merge Policy Rules.
In some cases, especially in environments with many forests and constantly changing content across many of the forests, an alternative to disabling merges is to set one or more forests to be delete-only. For details, see Making a Forest Delete-Only.