The inbound notifications on a provisioning server represent all of the data that the provisioning tier needs to send to the application server tier of Identity Manager. Without these notifications, any changes that occur on endpoints or in provisioning manager (such as a password change) will not be reflected in the IM Web UI or your Corporate User Store. When you u multiple Provisioning Servers in an Identity Manager environment, the notification queues will not be the same size and may process at different speeds.
Does Identity Manager load balance or sort notifications between notification queues for sending data from provisioning up to the application server tier?
Whichever Provisioning Server performs the operation will generate the notification and place it under the container named after itself. Each Provisioning Server will only process their own notifications (i.e. pull from the container named after itself).
Identity Manager does not do any load-balancing. Identity Manager has a primary Provisioning Server (any additional Provisioning Servers are failover only). We do not support trying to load-balance the provisioning servers as you can cause race conditions. If Identity Manager is executing Explore/Correlates those will get sent to the primary Provisioning Server and notifications will get generated on that Provisioning Server.