CAJ | 학술논문

　　针对分布式文件系统应用于海量小文件访问模式时，元数据请求过多导致系统性能下降的问题，提出了客户端元数据缓存授权机制的解决方案.客户端从服务器读取元数据时，申请相应类型的授权，服务器分析请求并决定是否授予此客户端所访问的元数据的授权.若客户端成功获取授权，则将其与本地缓存的元数据相关联，作为缓冲有效性的凭证.当再次访问本地缓存的元数据时，若有相关授权，则可以直接从本地获取元数据，无需向服务器发送缓存数据的有效性验证 RPC.仿真实验表明，文中的方法有效的降低了客户端发送元数据请求RPC的数量，节省了宝贵的网络带宽资源，降低了元数据服务器的负载.
　　침대분포식문건계통응용우해량소문건방문모식시，원수거청구과다도치계통성능하강적문제，제출료객호단원수거완존수권궤제적해결방안.객호단종복무기독취원수거시，신청상응류형적수권，복무기분석청구병결정시부수여차객호단소방문적원수거적수권.약객호단성공획취수권，칙장기여본지완존적원수거상관련，작위완충유효성적빙증.당재차방문본지완존적원수거시，약유상관수권，칙가이직접종본지획취원수거，무수향복무기발송완존수거적유효성험증 RPC.방진실험표명，문중적방법유효적강저료객호단발송원수거청구RPC적수량，절성료보귀적망락대관자원，강저료원수거복무기적부재.
Aiming at the system performance degradation problems of distributed file system in massive small file access patterns, designed and implemented a delegation mechanism for meta data cache in client .The client apply some kinds of delegations when getting meta data from the server. The meta data server checked and decided ecide whether to grant the delegation or not. Once the client getting the delegation which is stored in the local memory, the meta data getting operation can be unnecessary to sent RPC request. The simulation result shows that our method in this paper can reduce the number of the RPC request effectively, and aving valuable network bandwidth resources, reducing the metadata server load.