nbdkit-rotational-filter - Man Page

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

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.

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.

$filterdir/nbdkit-rotational-filter.so

The filter.

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

nbdkit-rotational-filter first appeared in nbdkit 1.40.

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.

Richard W.M. Jones

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nbdkit(1), nbdkit-filter(3), nbdkit-release-notes-1.40(1), nbdkit-spinning-filter(1).