* Made the profiler work in HipHop:

** Don't try to set a global variable in the same file as a class definition (Profiler.php). Set it in WebStart.php instead.
** In StartProfiler.sample, don't use require_once() to get ProfilerStub.

* Removed the setproctitle() stuff from ProfilerStub, the extension is not maintained and doesn't work with Apache 2.x
* Added an optimisation to wfProfileIn() and wfProfileOut() to reduce the overhead when profiling is not enabled
* Added the ability to configure in StartProfiler.php whether CPU time or wall-clock time is used, avoiding recompilation

StartProfiler.sample

@@ -1,10 +1,8 @@
 <?php
 
-require_once( dirname( __FILE__ ) . '/includes/profiler/ProfilerStub.php' );
-
 /**
  * To use a profiler, copy this file to StartProfiler.php,
- * delete the PHP line above, and add something like this:
+ * and add something like this:
  *
  *   $wgProfiler['class'] = 'Profiler';
  *

includes/WebStart.php

@@ -81,17 +81,19 @@ if ( isset( $_SERVER['MW_COMPILED'] ) ) {
 	# Start the autoloader, so that extensions can derive classes from core files
 	require_once( "$IP/includes/AutoLoader.php" );
 
-	# Start profiler
-	# @todo FIXME: Rewrite wfProfileIn/wfProfileOut so that they can work in compiled mode
+	# Load the profiler
 	require_once( "$IP/includes/profiler/Profiler.php" );
-	if ( file_exists( "$IP/StartProfiler.php" ) ) {
-		require_once( "$IP/StartProfiler.php" );
-	}
 
 	# Load up some global defines.
 	require_once( "$IP/includes/Defines.php" );
 }
 
+# Start the profiler
+$wgProfiler = array();
+if ( file_exists( "$IP/StartProfiler.php" ) ) {
+	require( "$IP/StartProfiler.php" );
+}
+
 wfProfileIn( 'WebStart.php-conf' );
 
 # Load default settings

includes/profiler/Profiler.php

@@ -7,21 +7,15 @@
  * This file is only included if profiling is enabled
  */
 
-/**
- * Default profiling configuration. Permitted keys are:
- *   class   : Name of Profiler or subclass to use for profiling
- *   visible : Whether to output the profile info [ProfilerSimpleText only]
- */
-$wgProfiler = array(
-	'class' => 'ProfilerStub',
-);
-
 /**
  * Begin profiling of a function
  * @param $functionname String: name of the function we will profile
  */
 function wfProfileIn( $functionname ) {
-	Profiler::instance()->profileIn( $functionname );
+	global $wgProfiler;
+	if ( isset( $wgProfiler['class'] ) ) {
+		Profiler::instance()->profileIn( $functionname );
+	}
 }
 
 /**
@@ -29,7 +23,10 @@ function wfProfileIn( $functionname ) {
  * @param $functionname String: name of the function we have profiled
  */
 function wfProfileOut( $functionname = 'missing' ) {
-	Profiler::instance()->profileOut( $functionname );
+	global $wgProfiler;
+	if ( isset( $wgProfiler['class'] ) ) {
+		Profiler::instance()->profileOut( $functionname );
+	}
 }
 
 /**
@@ -40,11 +37,12 @@ class Profiler {
 	var $mStack = array (), $mWorkStack = array (), $mCollated = array ();
 	var $mCalls = array (), $mTotals = array ();
 	var $mTemplated = false;
+	var $mTimeMetric = 'wall';
 	private $mCollateDone = false;
 	protected $mProfileID = false;
 	private static $__instance = null;
 
-	function __construct() {
+	function __construct( $params ) {
 		// Push an entry for the pre-profile setup time onto the stack
 		global $wgRequestTime;
 		if ( !empty( $wgRequestTime ) ) {
@@ -53,6 +51,9 @@ class Profiler {
 		} else {
 			$this->profileIn( '-total' );
 		}
+		if ( isset( $params['timeMetric'] ) ) {
+			$this->mTimeMetric = $params['timeMetric'];
+		}
 	}
 
 	/**
@@ -63,14 +64,13 @@ class Profiler {
 		if( is_null( self::$__instance ) ) {
 			global $wgProfiler;
 			if( is_array( $wgProfiler ) ) {
-				$class = $wgProfiler['class'];
+				$class = isset( $wgProfiler['class'] ) ? $wgProfiler['class'] : 'ProfilerStub';
 				self::$__instance = new $class( $wgProfiler );
 			} elseif( $wgProfiler instanceof Profiler ) {
 				self::$__instance = $wgProfiler; // back-compat
 			} else {
 				self::$__instance = new ProfilerStub;
 			}
-			
 		}
 		return self::$__instance;
 	}
@@ -253,8 +253,11 @@ class Profiler {
 	}
 
 	function getTime() {
-		return microtime(true);
-		#return $this->getUserTime();
+		if ( $this->mTimeMetric === 'user' ) {
+			return $this->getUserTime();
+		} else {
+			return microtime(true);
+		}
 	}
 
 	function getUserTime() {
@@ -474,7 +477,7 @@ class Profiler {
 	 * @param $s String to output
 	 */
 	function debug( $s ) {
-		if( function_exists( 'wfDebug' ) ) {
+		if( defined( 'MW_COMPILED' ) || function_exists( 'wfDebug' ) ) {
 			wfDebug( $s );
 		}
 	}

includes/profiler/ProfilerStub.php

@@ -5,57 +5,11 @@
  * @ingroup Profiler
  */
 class ProfilerStub extends Profiler {
-
-	/**
-	 * is setproctitle function available?
-	 * @var bool
-	 */
-	private $haveProctitle;
-	private $hackWhere = array();
-
-	/**
-	 * Constructor. Check for proctitle.
-	 */
-	public function __construct() {
-		$this->haveProctitle = function_exists( 'setproctitle' );
-	}
-
 	public function isStub() {
 		return true;
 	}
-
-	/**
-	 * Begin profiling of a function
-	 * @param $fn string
-	 */
-	public function profileIn( $fn ) {
-		global $wgDBname;
-		if( $this->haveProctitle ){
-			$this->hackWhere[] = $fn;
-			setproctitle( $fn . " [$wgDBname]" );
-		}
-	}
-
-	/**
-	 * Stop profiling of a function
-	 * @param $fn string
-	 */
-	public function profileOut( $fn ) {
-		global $wgDBname;
-		if( !$this->haveProctitle ) {
-			return;
-		}
-		if( count( $this->hackWhere ) ) {
-			array_pop( $this->hackWhere );
-		}
-		if( count( $this->hackWhere ) ) {
-			setproctitle( $this->hackWhere[count( $this->hackWhere )-1] . " [$wgDBname]" );
-		}
-	}
-
-	/**
-	 * Does nothing, just for compatibility
-	 */
+	public function profileIn( $fn ) {}
+	public function profileOut( $fn ) {}
 	public function getOutput() {}
 	public function close() {}
 }