基于FUSE提供POSIX兼容⽂件接⼝ • 问题 • 相对kernel⽂件系统的实现(ext4, xfs)性能 差异⼤，延迟⾼FUSE⽂件IO读写流程 • 场景1 pytorch example word_language_model • LOOKUP inode 返回 fstat + timeout设置 • OPEN 打开 inode返回ok • GETATTR 返回fstat ceph / gluster • LD_PRELOAD重载⽂件系统系统调⽤ • vpp / f-stack / DirectFUSE • Kernel版本实现 • BentoFS 基于rust的实现采⽤LD_Preload⽅式瓶颈分析 • 环境 • FUSE daemon使⽤ passthrough_ll 调⽤底层ext4 • 进程共享内存通信延迟10us+ • others

a file. For example, block device /dev/sda corresponds to file /foo/bar in CurveBS 2. The address space of the block device /dev/sda maps to chunks of file in the system. For example, chunk1 corresponds replication group membership is saved for each chunk, the number of metadata will be large. 2. Example Reduce the number of replication groups. The size of chunk is usually small, such as 16MB by default RAFT Node of BRaft and implements the user state machine of BRaft. Take a write request as an example 1. The Client sends the request to the ChunkServer where the replication group Leader resides

‘allow_other’ ；或者可以在用户态文件系统中自由的实现访问控制策略。 可以达到共享文件系统下的基于内核权限检查的文件访问控制 二、文件系统权限管理© XXX Page 16 of 33 // example in linux // --------- drwxr-xr-x 3 wanghai01 neteaseusers 4096 Jul 16 10:41 . drwx------ 17 wanghai01 Entry定义了特定的类别可以对文件拥有的操作权限。Access Entry有三个组成部分：Entry tag type, qualifier (optional), permission。 # example an Access Entry user:john:rw- group:dev:r-- 1. Entry tag type: ACL_USER_OBJLinuxfile_ownerpermission