HP JFS 3.3 and HP OnLineJFS 3.3 VERITAS File System 3.3 System Administrator's Guide

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onto any of the physical addresses available on a system.
preallocation A method of allowing an application to guarantee that
a specified amount of space is available for a file, even if the file system is
otherwise out of space.
primary fileset The files that are visible and accessible to the user.
quotas Quota limits on system resources for individual users for file and
data block usage on a file system. See hard limit and soft limit .
quotas file The quotas commands read and write the external quotas
file to get or change usage limits. When quotas are turned on, the quota
limits are copied from the external quotas file to the internal quotas file.
See quotas , internal quotas file , and external quotas file .
reservation An extent attribute used to preallocate space for a file.
snapshot file system An exact copy of a mounted file system at a
specific point in time. Used to do online backups.
snapped file system A file system whose exact image has been used
to create a snapshot file system.
soft limit The soft limit is lower than a hard limit. The soft limit can be
exceeded for a limited time. There are separate time limits for files and
blocks. See hard limit and quota .
storage checkpoint A facility that provides a consistent and stable
view of a file system or database image and keeps track of modified data
blocks since the last checkpoint.
structural fileset The files that define the structure of the file
system. These files are not visible or accessible to the user.
super-block A block containing critical information about the file
system such as the file system type, layout, and size. The VxFS
super-block is always located 8192 bytes from the beginning of the file
system and is 8192 bytes long.
synchronous writes A form of synchronous I/O that writes the file
data to disk, updates the inode times, and writes the updated inode to