A search system can maintain a search index of metadata and text for objects in a repository, repositories or distributed across a network. The search index can be divided into partitions with a partition assigned a first capacity utilization threshold and a second capacity utilization threshold. If the capacity utilization of the partition is below the first threshold, the system can add, update and delete information in the partition. If the capacity utilization of the partition is above the first threshold, the system can update and delete information in the partition, but cannot add information for new objects to the partition. If the capacity utilization of the partition is above the second threshold, the system can enter a rebalancing mode in which it seeks to rebalance capacity utilization between partitions. The behavior of the system can change depending upon the size of a partition relative to its configurable thresholds.