nbdkit-rotational-filter(1)

NAME
nbdkit-rotational-filter - set if a plugin is rotational or not

SYNOPSIS
 nbdkit --filter=rotational PLUGIN [rotational=true|false]

DESCRIPTION
"nbdkit-rotational-filter" is a filter for nbdkit(1) which lets you change the rotational property of a plugin.

The rotational property is a boolean flag which hints to the client whether the plugin behaves like a spinning disk (if rotational is true) or like a solid state disk or RAM (if rotational is false). If a disk is rotational, then the client may attempt to schedule disk accesses to reduce seek times using the elevator algorithm (https://en.wikipedia.org/wiki/Elevator_algorithm).

Adding this filter without using the "rotational" parameter forces the plugin to advertise that it is rotational. You can explicitly set the rotational property by using "rotational=true" or "rotational=false".

PARAMETERS

rotational=true
    Set the rotational property, indicating that the plugin behaves like a spinning disk. This is the default when you enable this filter.

rotational=false
    Clear the rotational property, indicating that the plugin behaves like a solid state disk or RAM.

FILES

$filterdir/nbdkit-rotational-filter.so
    The filter.

    Use "nbdkit --dump-config" to find the location of $filterdir.

VERSION
"nbdkit-rotational-filter" first appeared in nbdkit 1.40.

SEE ALSO
nbdkit(1), nbdkit-file-plugin(1), nbdkit-readonly-filter(1), nbdkit-spinning-filter(1), nbdinfo(1), nbdkit-filter(3), https://en.wikipedia.org/wiki/Elevator_algorithm.

AUTHORS
Richard W.M. Jones

COPYRIGHT
Copyright Red Hat

LICENSE
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

•   Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.

•   Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

•   Neither the name of Red Hat nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

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