(PHP >= 5.3.0)
XSLTProcessor::setProfiling — Sets profiling output file
$filename
   )Sets the file to output profiling information when processing a stylesheet.
filenamePath to the file to dump profiling information.
   Returns TRUE on success or FALSE on failure.
  
Example #1 Example profiling output
<?php
// Load the XML source
$xml = new DOMDocument;
$xml->load('collection.xml');
$xsl = new DOMDocument;
$xsl->load('collection.xsl');
// Configure the transformer
$proc = new XSLTProcessor;
$proc->setProfiling('profiling.txt');
$proc->importStyleSheet($xsl); // attach the xsl rules
echo trim($proc->transformToDoc($xml)->firstChild->wholeText);
?>
The above code will produce the following information in the profiling file:
number               match                name      mode  Calls Tot 100us Avg
    0                   cd                                    2      3      1
    1           collection                                    1      1      1
                         Total                                3      4