In order to improve the performance of the DNS server, a mathematical model based on M/M/c queue theory was proposed. The probability distribution function of response time was analyzed according to this model, which identifies domain name compression rate as the performance bottleneck. Due to the rule of traditional domain name compression algorithm, DNS servers can only perform real-time domain name compression when the query is answered, which causes a performance problem in the high-traffic scenario. To improve the domain name compression rate, the principle of domain name compression was analyzed from the aspects of DNS data characteristics. Based on this, combing with base relocation technology, a new domain name compression algorithm was proposed. The new design changes the traditional DNS data process, which reduces the real-time consumption during response by pre-compressing. Experimental results show that the algorithm improves the system resource utilization under the condition of small compression loss and achieves the goal of optimizing the percentile response time.