Today telecom network are growing complex. Although the amount of network performance data increased dramatically, telecom network operators require better performance on network performance data collection and analysis. Database is the important component in modern network management model. Since Main Memory DataBase (MMDB) store data in main physical memory and provide very high-speed access, MMDB can suffice the requirements on data intensive and real time response in network performance management system. This paper presents a novel lightweight design on MMDB for network performance data persistence.