A database management system in which a plurality of nodes form a database
instance, each node including a communication manager for dynamically
configuring inter-nodal communication resources. The communication
manager receives communication resource allocation requests from clients
or a self-tuning algorithm. A resource self-tuning mechanism allocates or
de-allocates memory blocks used for communication resource elements
dynamically in real time without cycling the instance. Memory blocks are
de-allocated asynchronously by placing associated communication resource
elements in quarantine until all communication resource elements
associated with the memory block are quarantined.