Predefined Constants
APD Functions
APD
PHP Manual

# Examples

## How to use PHP-APD in your scripts

1. As the first line of your PHP script, call the apd_set_pprof_trace() function to start the trace:

   `apd_set_pprof_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.

2. Now run your script. The dump output will be written to apd.dumpdir/pprof_pid.ext.

   Tip

   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`

3. 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:

       bash-2.05b$ pprofp -R /tmp/pprof.22141.0

       Trace for /home/dan/testapd.php
       Total Elapsed Time = 0.00
       Total System Time  = 0.00
       Total User Time    = 0.00

       Real         User        System             secs/    cumm
       %Time (excl/cumm)  (excl/cumm)  (excl/cumm) Calls    call    s/call  Memory Usage Name
       --------------------------------------------------------------------------------------
       100.0 0.00 0.00  0.00 0.00  0.00 0.00     1  0.0000   0.0009            0 main
       56.9 0.00 0.00  0.00 0.00  0.00 0.00     1  0.0005   0.0005            0 apd_set_pprof_trace
       28.0 0.00 0.00  0.00 0.00  0.00 0.00    10  0.0000   0.0000            0 preg_replace
       14.3 0.00 0.00  0.00 0.00  0.00 0.00    10  0.0000   0.0000            0 str_replace

   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.

4. To generate a calltree file that you can import into the KCacheGrind profile analysis application, issue the pprof2calltree comand.

Predefined Constants
APD Functions
APD
PHP Manual