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Memoize::ExpireLRU(3) User Contributed Perl DocumentationMemoize::ExpireLRU(3)

NAME
       Memoize::ExpireLRU - Expiry plug-in for Memoize that adds LRU cache
       expiration

SYNOPSIS
	   use Memoize;

	   memoize('slow_function',
		   TIE => [Memoize::ExpireLRU,
			   CACHESIZE =>	n,
			  ]);

       Note that one need not "use" this module.  It will be found by the
       Memoize module.

       The argument to "CACHESIZE" must	be an integer.	Normally, this is all
       that is needed.	Additional options are available:

	       TUNECACHESIZE =>	m,
	       INSTANCE	     =>	'descriptive_name',
	       TIE	     =>	'[DB_File, $filename, O_RDWR | O_CREATE, 0666]'

DESCRIPTION
       For the theory of Memoization, please see the Memoize module
       documentation. This module implements an	expiry policy for Memoize that
       follows LRU semantics, that is, the last	n results, where n is
       specified as the	argument to the	"CACHESIZE" parameter, will be cached.

PERFORMANCE TUNING
       It is often quite difficult to determine	what size cache	will give
       optimal results for a given function. To	aid in determining this,
       ExpireLRU includes cache	tuning support.	Enabling this causes a
       definite	performance hit, but it	is often useful	before code is
       released	to production.

       To enable cache tuning support, simply specify the optional
       "TUNECACHESIZE" parameter with a	size greater than that of the
       "CACHESIZE" parameter.

       When the	program	exits, a set of	statistics will	be printed to stderr.
       If multiple routines have been memoized,	separate sets of statistics
       are printed for each routine. The default names are somewhat cryptic:
       this is the purpose of the "INSTANCE" parameter.	The value of this
       parameter will be used as the identifier	within the statistics report.

DIAGNOSTIC METHODS
       Two additional routines are available but not exported.
       Memoize::ExpireLRU::ShowStats returns a string identical	to the
       statistics report printed to STDERR at the end of the program if	test
       caches have been	enabled; Memoize::ExpireLRU::DumpCache takes the
       instance	name of	a memoized function as a parameter, and	returns	a
       string describing the current state of that instance.

SEE ALSO
       Memoize

REPOSITORY
       <https://github.com/neilb/Memoize-ExpireLRU>

AUTHOR
       Brent B.	Powers (B2Pi), Powers@B2Pi.com

COPYRIGHT AND LICENSE
       This software is	copyright (c) 1999 by Brent B. Powers.

       This is free software; you can redistribute it and/or modify it under
       the same	terms as the Perl 5 programming	language system	itself.

perl v5.32.1			  2016-07-06		 Memoize::ExpireLRU(3)

NAME | SYNOPSIS | DESCRIPTION | PERFORMANCE TUNING | DIAGNOSTIC METHODS | SEE ALSO | REPOSITORY | AUTHOR | COPYRIGHT AND LICENSE

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