中文摘要：

在对象存储系统中,数据由智能化的对象存储设备管理.当前,对象存储设备端主要提供对象接口,传统的设计主要由通用文件I/O来封装.但是,通用文件系统在管理平坦命名空间时,尤其在长期使用后性能退化严重.因此,提出基于扩展Hash的对象文件系统XOBFS（extensible hashing objectbased storage file system）,将磁盘空间划分成多个区域单元,区域中定长块分配策略与位图管理空闲块方式结合;对象属性用扩展Hash管理,在Hash桶中采用相同对象属性相邻存放策略.XOBFS应用在对象存储设备端,具有元数据规模小、长期使用性能不退化、对属性进行有效管理等特点.测试结果表明,基于大对象的XOBFS的吞吐率优于传统文件系统.

英文摘要：

With the increasing demand of high I O throughput,highly parallel data transfer and highly scalable storage system,especially in the supercomputing field,the traditional storage system has been difficult to meet the requirements.OBS（object-based storage）system is a new network storage architecture.In OBS system,local storage space allocation is managed by intelligent OSD（object-based storage device）,and at present,the OSD is mainly managed by the common file system.However,when the common file system deals with the flat namespace,especially in the course of long-term use,the performance degenerates seriously.In this paper a new file system is proposed.XOBFS,which stands for extensible hashing object-based storage file system,uses fixed-length block allocation strategy and manages free block bitmap combination.Based on expanding hash manage object attribute,the same object attributes are stored in adjacent hash bucket.XOBFS applied in OSD has a lot of advantages.For example,the metadata has small scale,long-term performance is not degraded,and attribute of the object is managed effectively and so on.Test results show that big-object based XOBFS throughput rate is better than that of the traditional file system.XOBFS provides an effective method for storage management in OSD.