VERITAS File SystemÖ 3.5 (HP OnlineJFS/JFS3.5) AdministratorÆs Guide (December 2002)

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latency For file systems, this typically refers to the amount of time it takes a given file system operation to
return to the user.
local mounted file system A file system mounted on a single host. The single host mediates all file system
writes to storage from other clients. To be a local mount, a file system cannot be mounted using the mount -o
cluster option. See cluster mounted file system.
metadata Structural data describing the attributes of files on a disk.
MB Megabyte (2
20
bytes or 1024 kilobytes).
mirror A duplicate copy of a volume and the data therein (in the form of an ordered collection of subdisks).
Each mirror is one copy of the volume with which the mirror is associated.
node One of the hosts in a cluster.
node abort A situation where a node leaves a cluster (on an emergency basis) without attempting to stop
ongoing operations.
node join The process through which a node joins a cluster and gains access to shared disks.
object location table (OLT) The information needed to locate important file system structural elements.
The OLT is written to a fixed location on the underlying media (or disk).
object location table replica A copy of the OLT in case of data corruption. The OLT replica is written to a
fixed location on the underlying media (or disk).
page file A fixed-size block of virtual address space that can be mapped 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.
Quick I/O file A regular VxFS file that is accessed using the ::cdev:vxfs: extension.
Quick I/O for Databases Quick I/O is a VERITAS File System feature that improves database performance
by minimizing read/write locking and eliminating double buffering of data. This allows online transactions to
be processed at speeds equivalent to that of using raw disk devices, while keeping the administrative benefits
of file systems.
QuickLog VERITAS QuickLog is a high performance mechanism for receiving and storing intent log
information for VxFS file systems. QuickLog increases performance by exporting intent log information to a
separate physical volume.
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.