nbdkit-rotational-filter - set if a plugin is rotational or not
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.
Set the rotational property, indicating that the plugin behaves like a spinning disk. This is the default when you enable this filter.
Clear the rotational property, indicating that the plugin behaves like a solid state disk or RAM.
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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