This glossary defines some of the terms and acronyms used in the AdvFS documentation.
The agent that issues commands and obtains system information for the AdvFS GUI.
See advfsd. The agent runs in the traditional style of the UNIX daemon.
The time interval between agent scans of the system disk.
Guarantees that all data in a write system call (up to 8192 bytes) is either written to the disk or none of the data is written to the disk.
To even the distribution of files between volumes of a file domain.
See BMT.
A 512-byte unit of disk storage. Sixteen blocks comprise a page.
Bitfile Metadata Table. An array of 8-kilobyte pages, each with a header and an array of mcells located on each volume. A BMT contains all metadata for all files that have storage on the volume.
The area of memory that contains the blocks of data waiting to be written to disk.
Blocks created during tape backup for error recovery.
A read-only copy of a fileset that is created to capture fileset data at a particular time. The contents of the clone fileset can be backed up while the original fileset remains available to users.
Storage that is physically adjacent on a disk volume.
The process by which original information is saved in a clone fileset when data in the original file is changed.
To make files and free space in a file domain more contiguous.
Data that has been written by the application, but the file system has cached it in memory so it has not yet been written to disk.
A condition that prevents further access to the file domain when corruption in the domain is detected. AdvFS allows the filesets in the file domain to be unmounted after a domain panic.
Domain Version Number. A number in the disk metadata that specifies file structure. Version 5.0 and later file domains contain a DVN of 4, while file domains created under earlier operating systems have a DVN of 3.
The AdvFS Graphical User Interface (GUI).
A directory that defines the file domains by providing a subdirectory for each file domain created on the system.
A file that identifies filesets that are to be mounted at system reboot.
Contiguous area of disk space allocated to a file. Simple files have one extent map; striped files have an extent map for every stripe segment.
A named pool of storage that contains one or more volumes. Each file domain must have at least one fileset.
A set of numbers that identify the file domain to the system.
See extent.
Created when a file uses only part of the last page (less than 8 kilobytes) of file storage allocated or has a total size of less than 8 kilobytes.
A hierarchy of directory and file names. A fileset represents a mountable portion of the directory hierarchy of the AdvFS file system.
A quota that limits the amount of disk storage that a fileset can consume or the number of files a fileset can contain.
A file that is used to allocate storage for files or file segments that are less than 8 kilobytes (one page). Using fragments reduces the amount of wasted disk space.
The period of time a quota's soft limit can be exceeded as long as the hard limit is not exceeded.
A graphical user interface.
The time interval between updates of the GUI window information.
The quota limit for disk block usage or number of files that cannot be exceeded.
An identifier for a UFS file; similar to an AdvFS file domain tag.
Logical Storage Manage is a volume management system that mirrors volumes and provides volume-level striping.
File structure information such as file attributes, extent maps, and fileset attributes.
To move files from one volume to another within a file domain.
To maintain identical copies of data on different disks, thus providing high data availability and improved disk read performance.
Maps areas of the volume that do not represent AdvFS metadata, such as the disk label and boot blocks.
NetWorker for Tru64 UNIX provides scheduled, online automated backup.
A volume, file domain, fileset, or clone fileset managed by the AdvFS GUI.
The AdvFS GUI hierarchical display of objects.
An allocation of 8 ilobytes of contiguous disk space (16 blocks).
A real-time performance monitoring, analysis and management application.
License to access Compaq Computer Corporation software.
A file that keeps track of number of files, disk block usage, and grace period per user ID or per group ID. Fileset quota information is stored within the fileset.
A directory that defines the location of all filesets in a file domain. Each file domain has one.
A collection of blocks created to save AdvFS backup information.
See stripe segment.
The quota value beyond which disk block usage or number of files is allowed only during the grace period.
A file whose pages do not all have allocated disk space.
Tracks free and allocated disk space. Each volume in a file domain contains one.
To distribute data across multiple disks in a disk array, thus improving I/O performance by allowing parallel access.
The portion of a striped file that resides on an AdvFS volume. A file striped across four volumes has four stripe segments. Segments can be migrated from one volume to another.
The log that records changes to metadata before the changes are written to disk. At regular intervals these changes are written to disk. The log is circular and is eventually overwritten.
The directory that contains the most recently deleted files from an attached directory. The trashcan directory is set up by each user for user files.
The dynamically allocated system buffer cache that holds file data and AdvFS metadata.
Anything that behaves like a UNIX block device. This can be a disk, disk partition, or logical volume.
The process by which the modifications to the file-structure information are completely written to a transaction log before the actual changes are written to disk. This process is used to ensure file system consistency in the event of a system failure.