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This tool contains simple wrappers for selected Prolog profiler tools.
This tool can be loaded using the query:
For sample queries, please see the
SCRIPT.txt file in the tool directory.
To test this tool, load the
| ?- logtalk_load(profiler(tester)).
Supported backend Prolog compilers
Currently, this tool supports the profilers provided with SICStus Prolog 4, SWI-Prolog, and YAP. The tool includes two files:
simple wrapper for the YAP count profiler
simple wrapper for the SICStus Prolog 4 profiler
Logtalk also supports the YAP tick profiler (using the latest YAP development
version) and the SWI-Prolog XPCE profiler. When using the XPCE profiler,
you can avoid profiling the Logtalk compiler (which is invoked e.g. when
you use the
::/2 message-sending operator at the top-level interpreter) by
compiling your code with the
optimize flag turned on:
?- set_logtalk_flag(optimize, on). true. ?- use_module(library(statistics)). true. ?- profile(... :: ...). ...
prolog_statistics:profile/1 is a meta-predicate, Logtalk will
compile its argument before calling it thanks to the
predicate definitions in the adapter file. Without this hook definition, you
would need to use instead (to avoid profiling the compiler itself):
?- logtalk << (prolog_statistics:profile(... :: ...)). ...
In either case, Don't forget, however, to load the
before using or compiling calls to the
profile/1 to allow the Logtalk
compiler to access its meta-predicate template.
The profiler support attempts to conceal internal Logtalk compiler/runtime
predicates and the generated entity predicates that implement predicate
inheritance. Calls to internal compiler and runtime predicates have functors
$lgt_. Calls to predicates with functors such as
_super, used to implement inheritance, may still be listed in
a few cases. Note that the time and the number of calls/redos of concealed
predicates is added to the caller predicates.
Compiling source code for profiling
In order to get user-level object and predicate names instead of compiler
generated internal names when using the SWI-Prolog and YAP profilers, you
code_prefix flag to a character other than the default
compiling your source code. For example:
?- set_logtalk_flag(code_prefix, '.').
See also the
settings-sample.lgt file for automating the necessary setup
at Logtalk startup.