includes/profiler/ProfilerStandard.php

   1 <?php
   2 /**
   3  * Common implementation class for profiling.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup Profiler
  22  */
  23
  24 /**
  25  * Standard profiler that tracks real time, cpu time, and memory deltas
  26  *
  27  * This supports profile reports, the debug toolbar, and high-contention
  28  * DB query warnings. This does not persist the profiling data though.
  29  *
  30  * @ingroup Profiler
  31  * @since 1.24
  32  */
  33 class ProfilerStandard extends Profiler {
  34         /** @var array List of resolved profile calls with start/end data */
  35         protected $stack = array();
  36         /** @var array Queue of open profile calls with start data */
  37         protected $workStack = array();
  38
  39         /** @var array Map of (function name => aggregate data array) */
  40         protected $collated = array();
  41         /** @var bool */
  42         protected $collateDone = false;
  43         /** @var bool Whether to collect the full stack trace or just aggregates */
  44         protected $collateOnly = true;
  45         /** @var array Cache of a standard broken collation entry */
  46         protected $errorEntry;
  47
  48         /**
  49          * @param array $params
  50          *   - initTotal : set to false to omit -total/-setup entries (which use request start time)
  51          */
  52         public function __construct( array $params ) {
  53                 parent::__construct( $params );
  54
  55                 if ( !isset( $params['initTotal'] ) || $params['initTotal'] ) {
  56                         $this->addInitialStack();
  57                 }
  58         }
  59
  60         /**
  61          * Add the inital item in the stack.
  62          */
  63         protected function addInitialStack() {
  64                 $this->errorEntry = $this->getErrorEntry();
  65
  66                 $initialTime = $this->getInitialTime( 'wall' );
  67                 $initialCpu = $this->getInitialTime( 'cpu' );
  68                 if ( $initialTime !== null && $initialCpu !== null ) {
  69                         $this->workStack[] = array( '-total', 0, $initialTime, $initialCpu, 0 );
  70                         if ( $this->collateOnly ) {
  71                                 $this->workStack[] = array( '-setup', 1, $initialTime, $initialCpu, 0 );
  72                                 $this->profileOut( '-setup' );
  73                         } else {
  74                                 $this->stack[] = array( '-setup', 1, $initialTime, $initialCpu, 0,
  75                                         $this->getTime( 'wall' ), $this->getTime( 'cpu' ), 0 );
  76                         }
  77                 } else {
  78                         $this->profileIn( '-total' );
  79                 }
  80         }
  81
  82         /**
  83          * @return array Initial collation entry
  84          */
  85         protected function getZeroEntry() {
  86                 return array(
  87                         'cpu'      => 0.0,
  88                         'cpu_sq'   => 0.0,
  89                         'real'     => 0.0,
  90                         'real_sq'  => 0.0,
  91                         'memory'   => 0,
  92                         'count'    => 0,
  93                         'min_cpu'  => 0.0,
  94                         'max_cpu'  => 0.0,
  95                         'min_real' => 0.0,
  96                         'max_real' => 0.0,
  97                         'periods'  => array(), // not filled if collateOnly
  98                         'overhead' => 0 // not filled if collateOnly
  99                 );
 100         }
 101
 102         /**
 103          * @return array Initial collation entry for errors
 104          */
 105         protected function getErrorEntry() {
 106                 $entry = $this->getZeroEntry();
 107                 $entry['count'] = 1;
 108                 return $entry;
 109         }
 110
 111         /**
 112          * Update the collation entry for a given method name
 113          *
 114          * @param string $name
 115          * @param float $elapsedCpu
 116          * @param float $elapsedReal
 117          * @param int $memChange
 118          * @param int $subcalls
 119          * @param array|null $period Map of ('start','end','memory','subcalls')
 120          */
 121         protected function updateEntry(
 122                 $name, $elapsedCpu, $elapsedReal, $memChange, $subcalls = 0, $period = null
 123         ) {
 124                 $entry =& $this->collated[$name];
 125                 if ( !is_array( $entry ) ) {
 126                         $entry = $this->getZeroEntry();
 127                         $this->collated[$name] =& $entry;
 128                 }
 129                 $entry['cpu'] += $elapsedCpu;
 130                 $entry['cpu_sq'] += $elapsedCpu * $elapsedCpu;
 131                 $entry['real'] += $elapsedReal;
 132                 $entry['real_sq'] += $elapsedReal * $elapsedReal;
 133                 $entry['memory'] += $memChange > 0 ? $memChange : 0;
 134                 $entry['count']++;
 135                 $entry['min_cpu'] = $elapsedCpu < $entry['min_cpu'] ? $elapsedCpu : $entry['min_cpu'];
 136                 $entry['max_cpu'] = $elapsedCpu > $entry['max_cpu'] ? $elapsedCpu : $entry['max_cpu'];
 137                 $entry['min_real'] = $elapsedReal < $entry['min_real'] ? $elapsedReal : $entry['min_real'];
 138                 $entry['max_real'] = $elapsedReal > $entry['max_real'] ? $elapsedReal : $entry['max_real'];
 139                 // Apply optional fields
 140                 $entry['overhead'] += $subcalls;
 141                 if ( $period ) {
 142                         $entry['periods'][] = $period;
 143                 }
 144         }
 145
 146         /**
 147          * Called by wfProfieIn()
 148          *
 149          * @param string $functionname
 150          */
 151         public function profileIn( $functionname ) {
 152                 global $wgDebugFunctionEntry;
 153
 154                 if ( $wgDebugFunctionEntry ) {
 155                         $this->debug( str_repeat( ' ', count( $this->workStack ) ) .
 156                                 'Entering ' . $functionname . "\n" );
 157                 }
 158
 159                 $this->workStack[] = array(
 160                         $functionname,
 161                         count( $this->workStack ),
 162                         $this->getTime( 'time' ),
 163                         $this->getTime( 'cpu' ),
 164                         memory_get_usage()
 165                 );
 166         }
 167
 168         /**
 169          * Called by wfProfieOut()
 170          *
 171          * @param string $functionname
 172          */
 173         public function profileOut( $functionname ) {
 174                 global $wgDebugFunctionEntry;
 175
 176                 if ( $wgDebugFunctionEntry ) {
 177                         $this->debug( str_repeat( ' ', count( $this->workStack ) - 1 ) .
 178                                 'Exiting ' . $functionname . "\n" );
 179                 }
 180
 181                 $item = array_pop( $this->workStack );
 182                 list( $ofname, /* $ocount */, $ortime, $octime, $omem ) = $item;
 183
 184                 if ( $item === null ) {
 185                         $this->debugGroup( 'profileerror', "Profiling error: $functionname" );
 186                 } else {
 187                         if ( $functionname === 'close' ) {
 188                                 if ( $ofname !== '-total' ) {
 189                                         $message = "Profile section ended by close(): {$ofname}";
 190                                         $this->debugGroup( 'profileerror', $message );
 191                                         if ( $this->collateOnly ) {
 192                                                 $this->collated[$message] = $this->errorEntry;
 193                                         } else {
 194                                                 $this->stack[] = array( $message, 0, 0.0, 0.0, 0, 0.0, 0.0, 0 );
 195                                         }
 196                                 }
 197                                 $functionname = $ofname;
 198                         } elseif ( $ofname !== $functionname ) {
 199                                 $message = "Profiling error: in({$ofname}), out($functionname)";
 200                                 $this->debugGroup( 'profileerror', $message );
 201                                 if ( $this->collateOnly ) {
 202                                         $this->collated[$message] = $this->errorEntry;
 203                                 } else {
 204                                         $this->stack[] = array( $message, 0, 0.0, 0.0, 0, 0.0, 0.0, 0 );
 205                                 }
 206                         }
 207                         $realTime = $this->getTime( 'wall' );
 208                         $cpuTime = $this->getTime( 'cpu' );
 209                         if ( $this->collateOnly ) {
 210                                 $elapsedcpu = $cpuTime - $octime;
 211                                 $elapsedreal = $realTime - $ortime;
 212                                 $memchange = memory_get_usage() - $omem;
 213                                 $this->updateEntry( $functionname, $elapsedcpu, $elapsedreal, $memchange );
 214                         } else {
 215                                 $this->stack[] = array_merge( $item,
 216                                         array( $realTime, $cpuTime,     memory_get_usage() ) );
 217                         }
 218                 }
 219         }
 220
 221         public function scopedProfileIn( $section ) {
 222                 $this->profileIn( $section );
 223
 224                 $that = $this;
 225                 return new ScopedCallback( function () use ( $that, $section ) {
 226                         $that->profileOut( $section );
 227                 } );
 228         }
 229
 230         /**
 231          * Close opened profiling sections
 232          */
 233         public function close() {
 234                 while ( count( $this->workStack ) ) {
 235                         $this->profileOut( 'close' );
 236                 }
 237         }
 238
 239         /**
 240          * Returns a profiling output to be stored in debug file
 241          *
 242          * @return string
 243          */
 244         public function getOutput() {
 245                 global $wgDebugFunctionEntry, $wgProfileCallTree;
 246
 247                 $wgDebugFunctionEntry = false; // hack
 248
 249                 if ( !count( $this->stack ) && !count( $this->collated ) ) {
 250                         return "No profiling output\n";
 251                 }
 252
 253                 if ( $wgProfileCallTree ) {
 254                         return $this->getCallTree();
 255                 } else {
 256                         return $this->getFunctionReport();
 257                 }
 258         }
 259
 260         /**
 261          * Returns a tree of function call instead of a list of functions
 262          * @return string
 263          */
 264         protected function getCallTree() {
 265                 return implode( '', array_map(
 266                         array( &$this, 'getCallTreeLine' ), $this->remapCallTree( $this->stack )
 267                 ) );
 268         }
 269
 270         /**
 271          * Recursive function the format the current profiling array into a tree
 272          *
 273          * @param array $stack Profiling array
 274          * @return array
 275          */
 276         protected function remapCallTree( array $stack ) {
 277                 if ( count( $stack ) < 2 ) {
 278                         return $stack;
 279                 }
 280                 $outputs = array();
 281                 for ( $max = count( $stack ) - 1; $max > 0; ) {
 282                         /* Find all items under this entry */
 283                         $level = $stack[$max][1];
 284                         $working = array();
 285                         for ( $i = $max -1; $i >= 0; $i-- ) {
 286                                 if ( $stack[$i][1] > $level ) {
 287                                         $working[] = $stack[$i];
 288                                 } else {
 289                                         break;
 290                                 }
 291                         }
 292                         $working = $this->remapCallTree( array_reverse( $working ) );
 293                         $output = array();
 294                         foreach ( $working as $item ) {
 295                                 array_push( $output, $item );
 296                         }
 297                         array_unshift( $output, $stack[$max] );
 298                         $max = $i;
 299
 300                         array_unshift( $outputs, $output );
 301                 }
 302                 $final = array();
 303                 foreach ( $outputs as $output ) {
 304                         foreach ( $output as $item ) {
 305                                 $final[] = $item;
 306                         }
 307                 }
 308                 return $final;
 309         }
 310
 311         /**
 312          * Callback to get a formatted line for the call tree
 313          * @param array $entry
 314          * @return string
 315          */
 316         protected function getCallTreeLine( $entry ) {
 317                 list( $fname, $level, $startreal, , , $endreal ) = $entry;
 318                 $delta = $endreal - $startreal;
 319                 $space = str_repeat( ' ', $level );
 320                 # The ugly double sprintf is to work around a PHP bug,
 321                 # which has been fixed in recent releases.
 322                 return sprintf( "%10s %s %s\n",
 323                         trim( sprintf( "%7.3f", $delta * 1000.0 ) ), $space, $fname );
 324         }
 325
 326         /**
 327          * Return the collated data, collating first if need be
 328          * @return array
 329          */
 330         public function getCollatedData() {
 331                 if ( !$this->collateDone ) {
 332                         $this->collateData();
 333                 }
 334                 return $this->collated;
 335         }
 336
 337         /**
 338          * Populate collated
 339          */
 340         protected function collateData() {
 341                 if ( $this->collateDone ) {
 342                         return;
 343                 }
 344                 $this->collateDone = true;
 345                 $this->close(); // set "-total" entry
 346
 347                 if ( $this->collateOnly ) {
 348                         return; // already collated as methods exited
 349                 }
 350
 351                 $this->collated = array();
 352
 353                 # Estimate profiling overhead
 354                 $profileCount = count( $this->stack );
 355                 self::calculateOverhead( $profileCount );
 356
 357                 # First, subtract the overhead!
 358                 $overheadTotal = $overheadMemory = $overheadInternal = array();
 359                 foreach ( $this->stack as $entry ) {
 360                         // $entry is (name,pos,rtime0,cputime0,mem0,rtime1,cputime1,mem1)
 361                         $fname = $entry[0];
 362                         $elapsed = $entry[5] - $entry[2];
 363                         $memchange = $entry[7] - $entry[4];
 364
 365                         if ( $fname === '-overhead-total' ) {
 366                                 $overheadTotal[] = $elapsed;
 367                                 $overheadMemory[] = max( 0, $memchange );
 368                         } elseif ( $fname === '-overhead-internal' ) {
 369                                 $overheadInternal[] = $elapsed;
 370                         }
 371                 }
 372                 $overheadTotal = $overheadTotal ?
 373                         array_sum( $overheadTotal ) / count( $overheadInternal ) : 0;
 374                 $overheadMemory = $overheadMemory ?
 375                         array_sum( $overheadMemory ) / count( $overheadInternal ) : 0;
 376                 $overheadInternal = $overheadInternal ?
 377                         array_sum( $overheadInternal ) / count( $overheadInternal ) : 0;
 378
 379                 # Collate
 380                 foreach ( $this->stack as $index => $entry ) {
 381                         // $entry is (name,pos,rtime0,cputime0,mem0,rtime1,cputime1,mem1)
 382                         $fname = $entry[0];
 383                         $elapsedCpu = $entry[6] - $entry[3];
 384                         $elapsedReal = $entry[5] - $entry[2];
 385                         $memchange = $entry[7] - $entry[4];
 386                         $subcalls = $this->calltreeCount( $this->stack, $index );
 387
 388                         if ( substr( $fname, 0, 9 ) !== '-overhead' ) {
 389                                 # Adjust for profiling overhead (except special values with elapsed=0
 390                                 if ( $elapsed ) {
 391                                         $elapsed -= $overheadInternal;
 392                                         $elapsed -= ( $subcalls * $overheadTotal );
 393                                         $memchange -= ( $subcalls * $overheadMemory );
 394                                 }
 395                         }
 396
 397                         $period = array( 'start' => $entry[2], 'end' => $entry[5],
 398                                 'memory' => $memchange, 'subcalls' => $subcalls );
 399                         $this->updateEntry( $fname, $elapsedCpu, $elapsedReal, $memchange, $subcalls, $period );
 400                 }
 401
 402                 $this->collated['-overhead-total']['count'] = $profileCount;
 403                 arsort( $this->collated, SORT_NUMERIC );
 404         }
 405
 406         /**
 407          * Returns a list of profiled functions.
 408          *
 409          * @return string
 410          */
 411         protected function getFunctionReport() {
 412                 $this->collateData();
 413
 414                 $width = 140;
 415                 $nameWidth = $width - 65;
 416                 $format = "%-{$nameWidth}s %6d %13.3f %13.3f %13.3f%% %9d  (%13.3f -%13.3f) [%d]\n";
 417                 $titleFormat = "%-{$nameWidth}s %6s %13s %13s %13s %9s\n";
 418                 $prof = "\nProfiling data\n";
 419                 $prof .= sprintf( $titleFormat, 'Name', 'Calls', 'Total', 'Each', '%', 'Mem' );
 420
 421                 $total = isset( $this->collated['-total'] )
 422                         ? $this->collated['-total']['real']
 423                         : 0;
 424
 425                 foreach ( $this->collated as $fname => $data ) {
 426                         $calls = $data['count'];
 427                         $percent = $total ? 100 * $data['real'] / $total : 0;
 428                         $memory = $data['memory'];
 429                         $prof .= sprintf( $format,
 430                                 substr( $fname, 0, $nameWidth ),
 431                                 $calls,
 432                                 (float)( $data['real'] * 1000 ),
 433                                 (float)( $data['real'] * 1000 ) / $calls,
 434                                 $percent,
 435                                 $memory,
 436                                 ( $data['min_real'] * 1000.0 ),
 437                                 ( $data['max_real'] * 1000.0 ),
 438                                 $data['overhead']
 439                         );
 440                 }
 441                 $prof .= "\nTotal: $total\n\n";
 442
 443                 return $prof;
 444         }
 445
 446         public function getFunctionStats() {
 447                 // This method is called before shutdown in the footer method on Skins.
 448                 // If some outer methods have not yet called wfProfileOut(), work around
 449                 // that by clearing anything in the work stack to just the "-total" entry.
 450                 // Collate after doing this so the results do not include profile errors.
 451                 if ( count( $this->workStack ) > 1 ) {
 452                         $oldWorkStack = $this->workStack;
 453                         $this->workStack = array( $this->workStack[0] ); // just the "-total" one
 454                 } else {
 455                         $oldWorkStack = null;
 456                 }
 457                 $this->collateData();
 458                 // If this trick is used, then the old work stack is swapped back afterwards
 459                 // and collateDone is reset to false. This means that logData() will still
 460                 // make use of all the method data since the missing wfProfileOut() calls
 461                 // should be made by the time it is called.
 462                 if ( $oldWorkStack ) {
 463                         $this->workStack = $oldWorkStack;
 464                         $this->collateDone = false;
 465                 }
 466
 467                 $totalCpu = isset( $this->collated['-total'] )
 468                         ? $this->collated['-total']['cpu']
 469                         : 0;
 470                 $totalReal = isset( $this->collated['-total'] )
 471                         ? $this->collated['-total']['real']
 472                         : 0;
 473                 $totalMem = isset( $this->collated['-total'] )
 474                         ? $this->collated['-total']['memory']
 475                         : 0;
 476
 477                 $profile = array();
 478                 foreach ( $this->collated as $fname => $data ) {
 479                         $profile[] = array(
 480                                 'name' => $fname,
 481                                 'calls' => $data['count'],
 482                                 'real' => $data['real'] * 1000,
 483                                 '%real' => $totalReal ? 100 * $data['real'] / $totalReal : 0,
 484                                 'cpu' => $data['cpu'] * 1000,
 485                                 '%cpu' => $totalCpu ? 100 * $data['cpu'] / $totalCpu : 0,
 486                                 'memory' => $data['memory'],
 487                                 '%memory' => $totalMem ? 100 * $data['memory'] / $totalMem : 0,
 488                                 'min' => $data['min_real'] * 1000,
 489                                 'max' => $data['max_real'] * 1000
 490                         );
 491                 }
 492
 493                 return $profile;
 494         }
 495
 496         /**
 497          * Dummy calls to wfProfileIn/wfProfileOut to calculate its overhead
 498          * @param int $profileCount
 499          */
 500         protected static function calculateOverhead( $profileCount ) {
 501                 wfProfileIn( '-overhead-total' );
 502                 for ( $i = 0; $i < $profileCount; $i++ ) {
 503                         wfProfileIn( '-overhead-internal' );
 504                         wfProfileOut( '-overhead-internal' );
 505                 }
 506                 wfProfileOut( '-overhead-total' );
 507         }
 508
 509         /**
 510          * Counts the number of profiled function calls sitting under
 511          * the given point in the call graph. Not the most efficient algo.
 512          *
 513          * @param array $stack
 514          * @param int $start
 515          * @return int
 516          */
 517         protected function calltreeCount( $stack, $start ) {
 518                 $level = $stack[$start][1];
 519                 $count = 0;
 520                 for ( $i = $start -1; $i >= 0 && $stack[$i][1] > $level; $i-- ) {
 521                         $count ++;
 522                 }
 523                 return $count;
 524         }
 525
 526         /**
 527          * Get the initial time of the request, based either on $wgRequestTime or
 528          * $wgRUstart. Will return null if not able to find data.
 529          *
 530          * @param string|bool $metric Metric to use, with the following possibilities:
 531          *   - user: User CPU time (without system calls)
 532          *   - cpu: Total CPU time (user and system calls)
 533          *   - wall (or any other string): elapsed time
 534          *   - false (default): will fall back to default metric
 535          * @return float|null
 536          */
 537         protected function getTime( $metric = 'wall' ) {
 538                 if ( $metric === 'cpu' || $metric === 'user' ) {
 539                         $ru = wfGetRusage();
 540                         if ( !$ru ) {
 541                                 return 0;
 542                         }
 543                         $time = $ru['ru_utime.tv_sec'] + $ru['ru_utime.tv_usec'] / 1e6;
 544                         if ( $metric === 'cpu' ) {
 545                                 # This is the time of system calls, added to the user time
 546                                 # it gives the total CPU time
 547                                 $time += $ru['ru_stime.tv_sec'] + $ru['ru_stime.tv_usec'] / 1e6;
 548                         }
 549                         return $time;
 550                 } else {
 551                         return microtime( true );
 552                 }
 553         }
 554
 555         /**
 556          * Get the initial time of the request, based either on $wgRequestTime or
 557          * $wgRUstart. Will return null if not able to find data.
 558          *
 559          * @param string|bool $metric Metric to use, with the following possibilities:
 560          *   - user: User CPU time (without system calls)
 561          *   - cpu: Total CPU time (user and system calls)
 562          *   - wall (or any other string): elapsed time
 563          *   - false (default): will fall back to default metric
 564          * @return float|null
 565          */
 566         protected function getInitialTime( $metric = 'wall' ) {
 567                 global $wgRequestTime, $wgRUstart;
 568
 569                 if ( $metric === 'cpu' || $metric === 'user' ) {
 570                         if ( !count( $wgRUstart ) ) {
 571                                 return null;
 572                         }
 573
 574                         $time = $wgRUstart['ru_utime.tv_sec'] + $wgRUstart['ru_utime.tv_usec'] / 1e6;
 575                         if ( $metric === 'cpu' ) {
 576                                 # This is the time of system calls, added to the user time
 577                                 # it gives the total CPU time
 578                                 $time += $wgRUstart['ru_stime.tv_sec'] + $wgRUstart['ru_stime.tv_usec'] / 1e6;
 579                         }
 580                         return $time;
 581                 } else {
 582                         if ( empty( $wgRequestTime ) ) {
 583                                 return null;
 584                         } else {
 585                                 return $wgRequestTime;
 586                         }
 587                 }
 588         }
 589
 590         /**
 591          * Add an entry in the debug log file
 592          *
 593          * @param string $s String to output
 594          */
 595         protected function debug( $s ) {
 596                 if ( function_exists( 'wfDebug' ) ) {
 597                         wfDebug( $s );
 598                 }
 599         }
 600
 601         /**
 602          * Add an entry in the debug log group
 603          *
 604          * @param string $group Group to send the message to
 605          * @param string $s String to output
 606          */
 607         protected function debugGroup( $group, $s ) {
 608                 if ( function_exists( 'wfDebugLog' ) ) {
 609                         wfDebugLog( $group, $s );
 610                 }
 611         }
 612 }