Advanced PHP debugger
APD
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APD is the Advanced PHP Debugger. It was written to provide profiling and
debugging capabilities for PHP code, as well as to provide the ability to
print out a full stack backtrace. APD supports interactive debugging, but
by default it writes data to trace files. It also offers event based
logging so that varying levels of information (including function calls,
arguments passed, timings, etc.) can be turned on or off for individual
scripts.
APD is a Zend Extension, modifying the way the internals of PHP handle
function calls, and thus may or may not be compatible with other Zend
Extensions (for example Zend Optimizer).
&reference.apd.configure;
&reference.apd.ini;
&reftitle.resources;
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&reftitle.constants;
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How to use PHP-APD in your scripts
As the first line of your PHP script, call the apd_set_pprof_trace() function
to start the trace:
You can insert the line anywhere in your script, but if you do not start
tracing at the beginning of your script you discard profile data that might
otherwise lead you to a performance bottleneck.
Now run your script. The dump output will be written to
apd.dumpdir/pprof_pid.ext.
If you're running the CGI version of PHP, you will need to add the '-e'
flag to enable extended information for apd to work properly. For
example:
php -e -f script.php
To display formatted profile data, issue the pprofp
command with the sort and display options of your choice. The formatted
output will look something like:
The -R option used in this example sorts the profile table by the amount
of real time the script spent executing a given function. The "cumm call"
column reveals how many times each function was called, and the "s/call"
column reveals how many seconds each call to the function required, on
average.
To generate a calltree file that you can import into the KCacheGrind
profile analysis application, issue the pprof2calltree
comand.
&reference.apd.functions;