Oracle Video server, Manual

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Oracle Video Server (OVS)
System Architecture 2-7
Write Consistency The MDS enforces write consistency on all MDS files:
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A file can be written by only one client at a time.
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A file cannot be renamed, removed, truncated, or locked into read-only mode
while it is being written.
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If a process fails while writing to a file, the MDS makes the file available to be
written by other processes after a few minutes.
Volumes
MDS files are stored in MDS volumes — named collections of disks. Each MDS
volume stores files in a flat namespace. The MDS provides quick access to a file
given a unique identifier, such as a filename, but is not meant to be a general
purpose file system with nested hierarchical subdirectories to search and browse.
Logical content provides that level of interaction.
Each volume has a table of contents that lists the files in the volume and their
locations on disk.
Striping Striping means dividing a file into pieces and storing each piece on a
different disk. Striping a file distributes access to the file across many disks, rather
than concentrating it on one, reducing requests for each disk and improving
performance when the file is accessed by many concurrent clients.
A stripe is a portion of a disk reserved for a single piece of a striped file. The size of
a stripe is called a stripe size. The stripe size is the same for every disk in the
volume.
Figure 2–2 identifies a single stripe on a disk.
Figure 2–2 A stripe
A Stripe