doc/developer-guide/cache-architecture/cache-tool.en.rst

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.. include:: ../../common.defs
.. default-domain:: cpp

.. _cache_tool:

Cache Tool
**********

Internals
=========

.. type:: Megabytes

   A :class:`Scalar` type with a scale of 2~20~.

.. type:: CacheStripeBlocks

   A :class:`Scalar` type with a scale of 2~27~. This represents the units in which storage is
   allocated to stripes.

.. class:: VolumeConfig

   A container for parsed cache volume configuration.

   .. class:: Data

      Configuration information for a single cache volume.

      .. member:: int _idx

         The volume index, 0 if not specified in the configuration.

      .. member:: int _percent

         Volume size if specified as a percentage, otherwise 0 if not specified.

      .. member:: Megabytes _size

         Volume size if specified as an explicit size, otherwise 0 if not specified.

      .. member:: CacheStripeBlocks _alloc

         Already allocated size, used during allocation computations.

.. class:: VolumeAllocator

   This class provides handling for allocating storage space to stripes based on volume configuration.

   .. class:: V

      Cache volume data for a single cache volume.

      .. member:: VolumeConfig::Data const & _config

         A reference to the (parsed) volume configuration for a single volume to be used for allocating
         storage to that cache volume.

   .. member:: std::vector<V> _av

      Cache volume data for all the volumes in the configuration.

   .. member:: VolumeConfig _vols

      The parsed cache volume configuration.