Shared File System (SFS) Architecture

SFS files are represented in storage using a pointer block structure that is similar to the EDF structure. Unlike EDF files, however, SFS files can span minidisks. That is, the blocks that make up an SFS file can reside on more than one minidisk within a file pool. A file pool is a collection of minidisks that is owned and manipulated by a file pool server machine. In SFS file architecture, the pointer blocks do not refer to physical disk locations. Instead, they are relative (or logical) numbers. The file pool server uses control data, which the server maintains, to find the appropriate minidisk blocks based on these logical numbers. All SFS files are formatted with 4KB blocks. See Manipulating SFS and Minidisk Files and Directories for more information on SFS.