:orphan:

.. title:: EVICTION_NRU

.. option:: CONFIG_EVICTION_NRU

*Not Recently Used (NRU) page eviction algorithm*

Type: ``bool``

Help
====

This implements a Not Recently Used page eviction algorithm.
A periodic timer will clear the accessed state of all virtual pages.
When a page frame needs to be evicted, the algorithm will prefer to
evict page frames using an ascending order of priority:

 - recently accessed, dirty
 - recently accessed, clean
 - not recently accessed, dirty
 - not recently accessed, clean

Direct dependencies
===================

\ :ref:`<choice EVICTION_CHOICE: Page frame eviction algorithms> <choice_469>`

*(Includes any dependencies from ifs and menus.)*

Kconfig definition
==================

.. highlight:: kconfig

At ``subsys/demand_paging/eviction/Kconfig:17``

Included via ``Kconfig:8`` → ``Kconfig.zephyr:34`` → ``subsys/Kconfig:61`` → ``subsys/demand_paging/Kconfig:7``

Menu path: (Top) → Sub Systems and OS Services → Demand Paging modules → Page frame eviction algorithms

.. parsed-literal::

    config EVICTION_NRU
    	bool "Not Recently Used (NRU) page eviction algorithm"
    	depends on \ :ref:`<choice EVICTION_CHOICE: Page frame eviction algorithms> <choice_469>`
    	help
    	  This implements a Not Recently Used page eviction algorithm.
    	  A periodic timer will clear the accessed state of all virtual pages.
    	  When a page frame needs to be evicted, the algorithm will prefer to
    	  evict page frames using an ascending order of priority:
	  
    	   - recently accessed, dirty
    	   - recently accessed, clean
    	   - not recently accessed, dirty
    	   - not recently accessed, clean

*(The 'depends on' condition includes propagated dependencies from ifs and menus.)*