Improving Connection Management of the OpenLDAP Directory Server

This paper describes our effort to improve the performance of the connection management subsystem of the OpenLDAP directory server. Two proposed architectures, the multi-listener and the lightweight listener architectures, will be described and compared to each other. This paper will also describe our effort to improve the synchronization of multiple threads by introducing a semaphore based resource control scheme. The new connection management schemes proposed in this paper made the OpenLDAP directory server perform better in the presence of long latency operations and reduces the overhead caused by unnecessary context switching and inefficient event polling.