* @file
*/
-use RunningStat\RunningStat;
-
/**
* Convenience class for working with XHProf
* <https://github.com/phacility/xhprof>. XHProf can be installed as a PECL
* package for use with PHP5 (Zend PHP) and is built-in to HHVM 3.3.0.
*
- * @author Bryan Davis <bd808@wikimedia.org>
- * @copyright © 2014 Bryan Davis and Wikimedia Foundation.
- * @since 1.25
+ * @since 1.28
*/
class Xhprof {
-
- /**
- * @var array $config
- */
- protected $config;
-
- /**
- * Hierarchical profiling data returned by xhprof.
- * @var array $hieraData
- */
- protected $hieraData;
-
/**
- * Per-function inclusive data.
- * @var array $inclusive
+ * @var bool $enabled Whether XHProf is currently running.
*/
- protected $inclusive;
+ protected static $enabled;
/**
- * Per-function inclusive and exclusive data.
- * @var array $complete
+ * Start xhprof profiler
*/
- protected $complete;
-
- /**
- * Configuration data can contain:
- * - flags: Optional flags to add additional information to the
- * profiling data collected.
- * (XHPROF_FLAGS_NO_BUILTINS, XHPROF_FLAGS_CPU,
- * XHPROF_FLAGS_MEMORY)
- * - exclude: Array of function names to exclude from profiling.
- * - include: Array of function names to include in profiling.
- * - sort: Key to sort per-function reports on.
- *
- * Note: When running under HHVM, xhprof will always behave as though the
- * XHPROF_FLAGS_NO_BUILTINS flag has been used unless the
- * Eval.JitEnableRenameFunction option is enabled for the HHVM process.
- *
- * @param array $config
- */
- public function __construct( array $config = array() ) {
- $this->config = array_merge(
- array(
- 'flags' => 0,
- 'exclude' => array(),
- 'include' => null,
- 'sort' => 'wt',
- ),
- $config
- );
-
- xhprof_enable( $this->config['flags'], array(
- 'ignored_functions' => $this->config['exclude']
- ) );
+ public static function isEnabled() {
+ return self::$enabled;
}
/**
- * Stop collecting profiling data.
- *
- * Only the first invocation of this method will effect the internal
- * object state. Subsequent calls will return the data collected by the
- * initial call.
- *
- * @return array Collected profiling data (possibly cached)
+ * Start xhprof profiler
*/
- public function stop() {
- if ( $this->hieraData === null ) {
- $this->hieraData = $this->pruneData( xhprof_disable() );
+ public static function enable( $flags = 0, $options = [] ) {
+ if ( self::isEnabled() ) {
+ throw new Exception( 'Xhprof profiling is already enabled.' );
}
- return $this->hieraData;
- }
-
- /**
- * Load raw data from a prior run for analysis.
- * Stops any existing data collection and clears internal caches.
- *
- * Any 'include' filters configured for this Xhprof instance will be
- * enforced on the data as it is loaded. 'exclude' filters will however
- * not be enforced as they are an XHProf intrinsic behavior.
- *
- * @param array $data
- * @see getRawData()
- */
- public function loadRawData( array $data ) {
- $this->stop();
- $this->inclusive = null;
- $this->complete = null;
- $this->hieraData = $this->pruneData( $data );
- }
-
- /**
- * Get raw data collected by xhprof.
- *
- * If data collection has not been stopped yet this method will halt
- * collection to gather the profiling data.
- *
- * Each key in the returned array is an edge label for the call graph in
- * the form "caller==>callee". There is once special case edge labled
- * simply "main()" which represents the global scope entry point of the
- * application.
- *
- * XHProf will collect different data depending on the flags that are used:
- * - ct: Number of matching events seen.
- * - wt: Inclusive elapsed wall time for this event in microseconds.
- * - cpu: Inclusive elapsed cpu time for this event in microseconds.
- * (XHPROF_FLAGS_CPU)
- * - mu: Delta of memory usage from start to end of callee in bytes.
- * (XHPROF_FLAGS_MEMORY)
- * - pmu: Delta of peak memory usage from start to end of callee in
- * bytes. (XHPROF_FLAGS_MEMORY)
- * - alloc: Delta of amount memory requested from malloc() by the callee,
- * in bytes. (XHPROF_FLAGS_MALLOC)
- * - free: Delta of amount of memory passed to free() by the callee, in
- * bytes. (XHPROF_FLAGS_MALLOC)
- *
- * @return array
- * @see stop()
- * @see getInclusiveMetrics()
- * @see getCompleteMetrics()
- */
- public function getRawData() {
- return $this->stop();
+ self::$enabled = true;
+ xhprof_enable( $flags, $options );
}
/**
- * Convert an xhprof data key into an array of ['parent', 'child']
- * function names.
- *
- * The resulting array is left padded with nulls, so a key
- * with no parent (eg 'main()') will return [null, 'function'].
+ * Stop xhprof profiler
*
- * @return array
+ * @return array|null xhprof data from the run, or null if xhprof was not running.
*/
- public static function splitKey( $key ) {
- return array_pad( explode( '==>', $key, 2 ), -2, null );
- }
-
- /**
- * Remove data for functions that are not included in the 'include'
- * configuration array.
- *
- * @param array $data Raw xhprof data
- * @return array
- */
- protected function pruneData( $data ) {
- if ( !$this->config['include'] ) {
- return $data;
- }
-
- $want = array_fill_keys( $this->config['include'], true );
- $want['main()'] = true;
-
- $keep = array();
- foreach ( $data as $key => $stats ) {
- list( $parent, $child ) = self::splitKey( $key );
- if ( isset( $want[$parent] ) || isset( $want[$child] ) ) {
- $keep[$key] = $stats;
- }
+ public static function disable() {
+ if ( self::isEnabled() ) {
+ self::$enabled = false;
+ return xhprof_disable();
}
- return $keep;
- }
-
- /**
- * Get the inclusive metrics for each function call. Inclusive metrics
- * for given function include the metrics for all functions that were
- * called from that function during the measurement period.
- *
- * If data collection has not been stopped yet this method will halt
- * collection to gather the profiling data.
- *
- * See getRawData() for a description of the metric that are returned for
- * each funcition call. The values for the wt, cpu, mu and pmu metrics are
- * arrays with these values:
- * - total: Cumulative value
- * - min: Minimum value
- * - mean: Mean (average) value
- * - max: Maximum value
- * - variance: Variance (spread) of the values
- *
- * @return array
- * @see getRawData()
- * @see getCompleteMetrics()
- */
- public function getInclusiveMetrics() {
- if ( $this->inclusive === null ) {
- // Make sure we have data to work with
- $this->stop();
-
- $main = $this->hieraData['main()'];
- $hasCpu = isset( $main['cpu'] );
- $hasMu = isset( $main['mu'] );
- $hasAlloc = isset( $main['alloc'] );
-
- $this->inclusive = array();
- foreach ( $this->hieraData as $key => $stats ) {
- list( $parent, $child ) = self::splitKey( $key );
- if ( !isset( $this->inclusive[$child] ) ) {
- $this->inclusive[$child] = array(
- 'ct' => 0,
- 'wt' => new RunningStat(),
- );
- if ( $hasCpu ) {
- $this->inclusive[$child]['cpu'] = new RunningStat();
- }
- if ( $hasMu ) {
- $this->inclusive[$child]['mu'] = new RunningStat();
- $this->inclusive[$child]['pmu'] = new RunningStat();
- }
- if ( $hasAlloc ) {
- $this->inclusive[$child]['alloc'] = new RunningStat();
- $this->inclusive[$child]['free'] = new RunningStat();
- }
- }
-
- $this->inclusive[$child]['ct'] += $stats['ct'];
- foreach ( $stats as $stat => $value ) {
- if ( $stat === 'ct' ) {
- continue;
- }
-
- if ( !isset( $this->inclusive[$child][$stat] ) ) {
- // Ignore unknown stats
- continue;
- }
-
- for ( $i = 0; $i < $stats['ct']; $i++ ) {
- $this->inclusive[$child][$stat]->addObservation(
- $value / $stats['ct']
- );
- }
- }
- }
-
- // Convert RunningStat instances to static arrays and add
- // percentage stats.
- foreach ( $this->inclusive as $func => $stats ) {
- foreach ( $stats as $name => $value ) {
- if ( $value instanceof RunningStat ) {
- $total = $value->m1 * $value->n;
- $percent = ( isset( $main[$name] ) && $main[$name] )
- ? 100 * $total / $main[$name]
- : 0;
- $this->inclusive[$func][$name] = array(
- 'total' => $total,
- 'min' => $value->min,
- 'mean' => $value->m1,
- 'max' => $value->max,
- 'variance' => $value->m2,
- 'percent' => $percent,
- );
- }
- }
- }
-
- uasort( $this->inclusive, self::makeSortFunction(
- $this->config['sort'], 'total'
- ) );
- }
- return $this->inclusive;
- }
-
- /**
- * Get the inclusive and exclusive metrics for each function call.
- *
- * If data collection has not been stopped yet this method will halt
- * collection to gather the profiling data.
- *
- * In addition to the normal data contained in the inclusive metrics, the
- * metrics have an additional 'exclusive' measurement which is the total
- * minus the totals of all child function calls.
- *
- * @return array
- * @see getRawData()
- * @see getInclusiveMetrics()
- */
- public function getCompleteMetrics() {
- if ( $this->complete === null ) {
- // Start with inclusive data
- $this->complete = $this->getInclusiveMetrics();
-
- foreach ( $this->complete as $func => $stats ) {
- foreach ( $stats as $stat => $value ) {
- if ( $stat === 'ct' ) {
- continue;
- }
- // Initialize exclusive data with inclusive totals
- $this->complete[$func][$stat]['exclusive'] = $value['total'];
- }
- // Add sapce for call tree information to be filled in later
- $this->complete[$func]['calls'] = array();
- $this->complete[$func]['subcalls'] = array();
- }
-
- foreach ( $this->hieraData as $key => $stats ) {
- list( $parent, $child ) = self::splitKey( $key );
- if ( $parent !== null ) {
- // Track call tree information
- $this->complete[$child]['calls'][$parent] = $stats;
- $this->complete[$parent]['subcalls'][$child] = $stats;
- }
-
- if ( isset( $this->complete[$parent] ) ) {
- // Deduct child inclusive data from exclusive data
- foreach ( $stats as $stat => $value ) {
- if ( $stat === 'ct' ) {
- continue;
- }
-
- if ( !isset( $this->complete[$parent][$stat] ) ) {
- // Ignore unknown stats
- continue;
- }
-
- $this->complete[$parent][$stat]['exclusive'] -= $value;
- }
- }
- }
-
- uasort( $this->complete, self::makeSortFunction(
- $this->config['sort'], 'exclusive'
- ) );
- }
- return $this->complete;
- }
-
- /**
- * Get a list of all callers of a given function.
- *
- * @param string $function Function name
- * @return array
- * @see getEdges()
- */
- public function getCallers( $function ) {
- $edges = $this->getCompleteMetrics();
- if ( isset( $edges[$function]['calls'] ) ) {
- return array_keys( $edges[$function]['calls'] );
- } else {
- return array();
- }
- }
-
- /**
- * Get a list of all callees from a given function.
- *
- * @param string $function Function name
- * @return array
- * @see getEdges()
- */
- public function getCallees( $function ) {
- $edges = $this->getCompleteMetrics();
- if ( isset( $edges[$function]['subcalls'] ) ) {
- return array_keys( $edges[$function]['subcalls'] );
- } else {
- return array();
- }
- }
-
- /**
- * Find the critical path for the given metric.
- *
- * @param string $metric Metric to find critical path for
- * @return array
- */
- public function getCriticalPath( $metric = 'wt' ) {
- $this->stop();
- $func = 'main()';
- $path = array(
- $func => $this->hieraData[$func],
- );
- while ( $func ) {
- $callees = $this->getCallees( $func );
- $maxCallee = null;
- $maxCall = null;
- foreach ( $callees as $callee ) {
- $call = "{$func}==>{$callee}";
- if ( $maxCall === null ||
- $this->hieraData[$call][$metric] >
- $this->hieraData[$maxCall][$metric]
- ) {
- $maxCallee = $callee;
- $maxCall = $call;
- }
- }
- if ( $maxCall !== null ) {
- $path[$maxCall] = $this->hieraData[$maxCall];
- }
- $func = $maxCallee;
- }
- return $path;
- }
-
- /**
- * Make a closure to use as a sort function. The resulting function will
- * sort by descending numeric values (largest value first).
- *
- * @param string $key Data key to sort on
- * @param string $sub Sub key to sort array values on
- * @return Closure
- */
- public static function makeSortFunction( $key, $sub ) {
- return function ( $a, $b ) use ( $key, $sub ) {
- if ( isset( $a[$key] ) && isset( $b[$key] ) ) {
- // Descending sort: larger values will be first in result.
- // Assumes all values are numeric.
- // Values for 'main()' will not have sub keys
- $valA = is_array( $a[$key] ) ? $a[$key][$sub] : $a[$key];
- $valB = is_array( $b[$key] ) ? $b[$key][$sub] : $b[$key];
- return $valB - $valA;
- } else {
- // Sort datum with the key before those without
- return isset( $a[$key] ) ? -1 : 1;
- }
- };
}
}