9.6. File Systems and the Kernel
The Unix virtual file system (VFS) supplies a standard interface to various physical file systems. On HP-UX, supported file systems include hfs (hierarchal UNIX file system, also called ufs or Unix File System), JFS ( Journaled File System, which is the Veritas VxFS), lofs (loopback file system), cdfs (Compact Disc File System), dosfs (FAT file system for floppy disks), and NFS (Network File System). NFS performance issues are discussed in detail in Chapter 10, ”Network Bottlenecks” on page 317. Tuning recommendations will be presented later in this chapter for HFS and JFS file systems only.
9.6.1. I/O-Related Kernel Tables
Figure 9-11 shows the kernel tables that describe files and file systems.