75b2645e3f
git-svn-id: https://yap.svn.sf.net/svnroot/yap/trunk@1580 b08c6af1-5177-4d33-ba66-4b1c6b8b522a
61 lines
2.9 KiB
Plaintext
61 lines
2.9 KiB
Plaintext
=================================================================
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Logtalk - Object oriented extension to Prolog
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Release 2.27.1
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Copyright (c) 1998-2006 Paulo Moura. All Rights Reserved.
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=================================================================
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To load this example and for sample queries, please see the SCRIPT file.
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This folder provides simple benchmark tests for comparing Logtalk message
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sending performance with direct predicates calls in plain Prolog.
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These benchmarks may also be used for comparing Logtalk message sending
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performance across Prolog compilers.
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This example is made of five source files:
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benchmark.lgt
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contains the benchmark predicates
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plain.lgt
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contains a definition for a list length predicate and a predicate
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for testing performance of the built-in predicates assertz/1 and
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retract/1
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module.pl (not loaded by default; see below)
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contains the same definition of a list length predicate
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encapsulated in a module
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object.lgt
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contains the same definition of a list length predicate
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encapsulated in an object
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database.lgt
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contains predicates for testing the performance of the built-in
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database methods assertz/1 and retract/1
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You may have noticed above that the benchmark predicates and the predicates
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for plain Prolog testing are both encapsulated in Logtalk source files. The
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Logtalk compiler just copies the plain Prolog code to the generated Prolog
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files. The reason for using the .lgt extension for these files is just to
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make it possible to load all the example code using a single call to the
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logtalk_load/1 predicate.
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By default, the benchmark tests on the SCRIPT file use a list of 30 elements
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as an argument to the list length predicates. Increasing the list length
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leads to decreasing performance differences between plain Prolog and Logtalk
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as the list length computation time far outweighs the overhead of the message
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sending mechanism. Likewise, decreasing the list length leads to increasing
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performance differences between plain Prolog and Logtalk (up to the point you
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will be measuring the Logtalk message sending mechanism overhead compared to
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plain Prolog predicate calls). In real-life applications, only testing can
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give you a balanced view on the trade-offs between plain Prolog performance
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and Logtalk programming features.
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By default, the loader.lgt file used to load the example code does not load
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the module.pl file. Edit this file if your Prolog compiler supports a module
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system and you want to run some comparative performance tests between plain
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Prolog, Prolog modules, and Logtalk objects. Note that you may need to edit
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the code on the module.pl file to make any necessary compatibility changes
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for your Prolog compiler module system. For most Prolog module systems, the
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performance of module calls is close or even identical to the performance of
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plain Prolog calls, specially when using imported predicates as opposed to
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using explicit module qualification.
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