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 $mStack = array();
  36         /** @var array Queue of open profile calls with start data */
  37         protected $mWorkStack = array();
  38
  39         /** @var array Map of (function name => aggregate data array) */
  40         protected $mCollated = array();
  41         /** @var bool */
  42         protected $mCollateDone = false;
  43         /** @var bool */
  44         protected $mCollateOnly = false;
  45         /** @var array Cache of a standard broken collation entry */
  46         protected $mErrorEntry;
  47
  48         /**
  49          * @param array $params
  50          */
  51         public function __construct( array $params ) {
  52                 parent::__construct( $params );
  53
  54                 $this->mCollateOnly = $this->collateOnly();
  55
  56                 $this->addInitialStack();
  57         }
  58
  59         /**
  60          * Return whether this a stub profiler
  61          *
  62          * @return bool
  63          */
  64         public function isStub() {
  65                 return false;
  66         }
  67
  68         /**
  69          * Return whether this profiler stores data
  70          *
  71          * @see Profiler::logData()
  72          * @return bool
  73          */
  74         public function isPersistent() {
  75                 return false;
  76         }
  77
  78         /**
  79          * Whether to internally just track aggregates and ignore the full stack trace
  80          *
  81          * Only doing collation saves memory overhead but limits the use of certain
  82          * features like that of graph generation for the debug toolbar.
  83          *
  84          * @return bool
  85          */
  86         protected function collateOnly() {
  87                 return false;
  88         }
  89
  90         /**
  91          * Add the inital item in the stack.
  92          */
  93         protected function addInitialStack() {
  94                 $this->mErrorEntry = $this->getErrorEntry();
  95
  96                 $initialTime = $this->getInitialTime( 'wall' );
  97                 $initialCpu = $this->getInitialTime( 'cpu' );
  98                 if ( $initialTime !== null && $initialCpu !== null ) {
  99                         $this->mWorkStack[] = array( '-total', 0, $initialTime, $initialCpu, 0 );
 100                         if ( $this->mCollateOnly ) {
 101                                 $this->mWorkStack[] = array( '-setup', 1, $initialTime, $initialCpu, 0 );
 102                                 $this->profileOut( '-setup' );
 103                         } else {
 104                                 $this->mStack[] = array( '-setup', 1, $initialTime, $initialCpu, 0,
 105                                         $this->getTime( 'wall' ), $this->getTime( 'cpu' ), 0 );
 106                         }
 107                 } else {
 108                         $this->profileIn( '-total' );
 109                 }
 110         }
 111
 112         /**
 113          * @return array Initial collation entry
 114          */
 115         protected function getZeroEntry() {
 116                 return array(
 117                         'cpu'      => 0.0,
 118                         'cpu_sq'   => 0.0,
 119                         'real'     => 0.0,
 120                         'real_sq'  => 0.0,
 121                         'memory'   => 0,
 122                         'count'    => 0,
 123                         'min_cpu'  => 0.0,
 124                         'max_cpu'  => 0.0,
 125                         'min_real' => 0.0,
 126                         'max_real' => 0.0,
 127                         'periods'  => array(), // not filled if mCollateOnly
 128                         'overhead' => 0 // not filled if mCollateOnly
 129                 );
 130         }
 131
 132         /**
 133          * @return array Initial collation entry for errors
 134          */
 135         protected function getErrorEntry() {
 136                 $entry = $this->getZeroEntry();
 137                 $entry['count'] = 1;
 138                 return $entry;
 139         }
 140
 141         /**
 142          * Update the collation entry for a given method name
 143          *
 144          * @param string $name
 145          * @param float $elapsedCpu
 146          * @param float $elapsedReal
 147          * @param int $memChange
 148          * @param int $subcalls
 149          * @param array|null $period Map of ('start','end','memory','subcalls')
 150          */
 151         protected function updateEntry(
 152                 $name, $elapsedCpu, $elapsedReal, $memChange, $subcalls = 0, $period = null
 153         ) {
 154                 $entry =& $this->mCollated[$name];
 155                 if ( !is_array( $entry ) ) {
 156                         $entry = $this->getZeroEntry();
 157                         $this->mCollated[$name] =& $entry;
 158                 }
 159                 $entry['cpu'] += $elapsedCpu;
 160                 $entry['cpu_sq'] += $elapsedCpu * $elapsedCpu;
 161                 $entry['real'] += $elapsedReal;
 162                 $entry['real_sq'] += $elapsedReal * $elapsedReal;
 163                 $entry['memory'] += $memChange > 0 ? $memChange : 0;
 164                 $entry['count']++;
 165                 $entry['min_cpu'] = $elapsedCpu < $entry['min_cpu'] ? $elapsedCpu : $entry['min_cpu'];
 166                 $entry['max_cpu'] = $elapsedCpu > $entry['max_cpu'] ? $elapsedCpu : $entry['max_cpu'];
 167                 $entry['min_real'] = $elapsedReal < $entry['min_real'] ? $elapsedReal : $entry['min_real'];
 168                 $entry['max_real'] = $elapsedReal > $entry['max_real'] ? $elapsedReal : $entry['max_real'];
 169                 // Apply optional fields
 170                 $entry['overhead'] += $subcalls;
 171                 if ( $period ) {
 172                         $entry['periods'][] = $period;
 173                 }
 174         }
 175
 176         /**
 177          * Called by wfProfieIn()
 178          *
 179          * @param string $functionname
 180          */
 181         public function profileIn( $functionname ) {
 182                 global $wgDebugFunctionEntry;
 183
 184                 if ( $wgDebugFunctionEntry ) {
 185                         $this->debug( str_repeat( ' ', count( $this->mWorkStack ) ) .
 186                                 'Entering ' . $functionname . "\n" );
 187                 }
 188
 189                 $this->mWorkStack[] = array(
 190                         $functionname,
 191                         count( $this->mWorkStack ),
 192                         $this->getTime( 'time' ),
 193                         $this->getTime( 'cpu' ),
 194                         memory_get_usage()
 195                 );
 196         }
 197
 198         /**
 199          * Called by wfProfieOut()
 200          *
 201          * @param string $functionname
 202          */
 203         public function profileOut( $functionname ) {
 204                 global $wgDebugFunctionEntry;
 205
 206                 if ( $wgDebugFunctionEntry ) {
 207                         $this->debug( str_repeat( ' ', count( $this->mWorkStack ) - 1 ) .
 208                                 'Exiting ' . $functionname . "\n" );
 209                 }
 210
 211                 $item = array_pop( $this->mWorkStack );
 212                 list( $ofname, /* $ocount */, $ortime, $octime, $omem ) = $item;
 213
 214                 if ( $item === null ) {
 215                         $this->debugGroup( 'profileerror', "Profiling error: $functionname" );
 216                 } else {
 217                         if ( $functionname === 'close' ) {
 218                                 if ( $ofname !== '-total' ) {
 219                                         $message = "Profile section ended by close(): {$ofname}";
 220                                         $this->debugGroup( 'profileerror', $message );
 221                                         if ( $this->mCollateOnly ) {
 222                                                 $this->mCollated[$message] = $this->mErrorEntry;
 223                                         } else {
 224                                                 $this->mStack[] = array( $message, 0, 0.0, 0.0, 0, 0.0, 0.0, 0 );
 225                                         }
 226                                 }
 227                                 $functionname = $ofname;
 228                         } elseif ( $ofname !== $functionname ) {
 229                                 $message = "Profiling error: in({$ofname}), out($functionname)";
 230                                 $this->debugGroup( 'profileerror', $message );
 231                                 if ( $this->mCollateOnly ) {
 232                                         $this->mCollated[$message] = $this->mErrorEntry;
 233                                 } else {
 234                                         $this->mStack[] = array( $message, 0, 0.0, 0.0, 0, 0.0, 0.0, 0 );
 235                                 }
 236                         }
 237                         $realTime = $this->getTime( 'wall' );
 238                         $cpuTime = $this->getTime( 'cpu' );
 239                         if ( $this->mCollateOnly ) {
 240                                 $elapsedcpu = $cpuTime - $octime;
 241                                 $elapsedreal = $realTime - $ortime;
 242                                 $memchange = memory_get_usage() - $omem;
 243                                 $this->updateEntry( $functionname, $elapsedcpu, $elapsedreal, $memchange );
 244                         } else {
 245                                 $this->mStack[] = array_merge( $item,
 246                                         array( $realTime, $cpuTime,     memory_get_usage() ) );
 247                         }
 248                         $this->trxProfiler->recordFunctionCompletion( $functionname, $realTime - $ortime );
 249                 }
 250         }
 251
 252         /**
 253          * Close opened profiling sections
 254          */
 255         public function close() {
 256                 while ( count( $this->mWorkStack ) ) {
 257                         $this->profileOut( 'close' );
 258                 }
 259         }
 260
 261         /**
 262          * Log the data to some store or even the page output
 263          */
 264         public function logData() {
 265                 /* Implement in subclasses */
 266         }
 267
 268         /**
 269          * Returns a profiling output to be stored in debug file
 270          *
 271          * @return string
 272          */
 273         public function getOutput() {
 274                 global $wgDebugFunctionEntry, $wgProfileCallTree;
 275
 276                 $wgDebugFunctionEntry = false; // hack
 277
 278                 if ( !count( $this->mStack ) && !count( $this->mCollated ) ) {
 279                         return "No profiling output\n";
 280                 }
 281
 282                 if ( $wgProfileCallTree ) {
 283                         return $this->getCallTree();
 284                 } else {
 285                         return $this->getFunctionReport();
 286                 }
 287         }
 288
 289         /**
 290          * Returns a tree of function call instead of a list of functions
 291          * @return string
 292          */
 293         protected function getCallTree() {
 294                 return implode( '', array_map(
 295                         array( &$this, 'getCallTreeLine' ), $this->remapCallTree( $this->mStack )
 296                 ) );
 297         }
 298
 299         /**
 300          * Recursive function the format the current profiling array into a tree
 301          *
 302          * @param array $stack profiling array
 303          * @return array
 304          */
 305         protected function remapCallTree( array $stack ) {
 306                 if ( count( $stack ) < 2 ) {
 307                         return $stack;
 308                 }
 309                 $outputs = array();
 310                 for ( $max = count( $stack ) - 1; $max > 0; ) {
 311                         /* Find all items under this entry */
 312                         $level = $stack[$max][1];
 313                         $working = array();
 314                         for ( $i = $max -1; $i >= 0; $i-- ) {
 315                                 if ( $stack[$i][1] > $level ) {
 316                                         $working[] = $stack[$i];
 317                                 } else {
 318                                         break;
 319                                 }
 320                         }
 321                         $working = $this->remapCallTree( array_reverse( $working ) );
 322                         $output = array();
 323                         foreach ( $working as $item ) {
 324                                 array_push( $output, $item );
 325                         }
 326                         array_unshift( $output, $stack[$max] );
 327                         $max = $i;
 328
 329                         array_unshift( $outputs, $output );
 330                 }
 331                 $final = array();
 332                 foreach ( $outputs as $output ) {
 333                         foreach ( $output as $item ) {
 334                                 $final[] = $item;
 335                         }
 336                 }
 337                 return $final;
 338         }
 339
 340         /**
 341          * Callback to get a formatted line for the call tree
 342          * @return string
 343          */
 344         protected function getCallTreeLine( $entry ) {
 345                 list( $fname, $level, $startreal, , , $endreal ) = $entry;
 346                 $delta = $endreal - $startreal;
 347                 $space = str_repeat( ' ', $level );
 348                 # The ugly double sprintf is to work around a PHP bug,
 349                 # which has been fixed in recent releases.
 350                 return sprintf( "%10s %s %s\n",
 351                         trim( sprintf( "%7.3f", $delta * 1000.0 ) ), $space, $fname );
 352         }
 353
 354         /**
 355          * Populate mCollated
 356          */
 357         protected function collateData() {
 358                 if ( $this->mCollateDone ) {
 359                         return;
 360                 }
 361                 $this->mCollateDone = true;
 362                 $this->close(); // set "-total" entry
 363
 364                 if ( $this->mCollateOnly ) {
 365                         return; // already collated as methods exited
 366                 }
 367
 368                 $this->mCollated = array();
 369
 370                 # Estimate profiling overhead
 371                 $profileCount = count( $this->mStack );
 372                 self::calculateOverhead( $profileCount );
 373
 374                 # First, subtract the overhead!
 375                 $overheadTotal = $overheadMemory = $overheadInternal = array();
 376                 foreach ( $this->mStack as $entry ) {
 377                         // $entry is (name,pos,rtime0,cputime0,mem0,rtime1,cputime1,mem1)
 378                         $fname = $entry[0];
 379                         $elapsed = $entry[5] - $entry[2];
 380                         $memchange = $entry[7] - $entry[4];
 381
 382                         if ( $fname === '-overhead-total' ) {
 383                                 $overheadTotal[] = $elapsed;
 384                                 $overheadMemory[] = max( 0, $memchange );
 385                         } elseif ( $fname === '-overhead-internal' ) {
 386                                 $overheadInternal[] = $elapsed;
 387                         }
 388                 }
 389                 $overheadTotal = $overheadTotal ?
 390                         array_sum( $overheadTotal ) / count( $overheadInternal ) : 0;
 391                 $overheadMemory = $overheadMemory ?
 392                         array_sum( $overheadMemory ) / count( $overheadInternal ) : 0;
 393                 $overheadInternal = $overheadInternal ?
 394                         array_sum( $overheadInternal ) / count( $overheadInternal ) : 0;
 395
 396                 # Collate
 397                 foreach ( $this->mStack as $index => $entry ) {
 398                         // $entry is (name,pos,rtime0,cputime0,mem0,rtime1,cputime1,mem1)
 399                         $fname = $entry[0];
 400                         $elapsedCpu = $entry[6] - $entry[3];
 401                         $elapsedReal = $entry[5] - $entry[2];
 402                         $memchange = $entry[7] - $entry[4];
 403                         $subcalls = $this->calltreeCount( $this->mStack, $index );
 404
 405                         if ( substr( $fname, 0, 9 ) !== '-overhead' ) {
 406                                 # Adjust for profiling overhead (except special values with elapsed=0
 407                                 if ( $elapsed ) {
 408                                         $elapsed -= $overheadInternal;
 409                                         $elapsed -= ( $subcalls * $overheadTotal );
 410                                         $memchange -= ( $subcalls * $overheadMemory );
 411                                 }
 412                         }
 413
 414                         $period = array( 'start' => $entry[2], 'end' => $entry[5],
 415                                 'memory' => $memchange, 'subcalls' => $subcalls );
 416                         $this->updateEntry( $fname, $elapsedCpu, $elapsedReal, $memchange, $subcalls, $period );
 417                 }
 418
 419                 $this->mCollated['-overhead-total']['count'] = $profileCount;
 420                 arsort( $this->mCollated, SORT_NUMERIC );
 421         }
 422
 423         /**
 424          * Returns a list of profiled functions.
 425          *
 426          * @return string
 427          */
 428         protected function getFunctionReport() {
 429                 $this->collateData();
 430
 431                 $width = 140;
 432                 $nameWidth = $width - 65;
 433                 $format = "%-{$nameWidth}s %6d %13.3f %13.3f %13.3f%% %9d  (%13.3f -%13.3f) [%d]\n";
 434                 $titleFormat = "%-{$nameWidth}s %6s %13s %13s %13s %9s\n";
 435                 $prof = "\nProfiling data\n";
 436                 $prof .= sprintf( $titleFormat, 'Name', 'Calls', 'Total', 'Each', '%', 'Mem' );
 437
 438                 $total = isset( $this->mCollated['-total'] )
 439                         ? $this->mCollated['-total']['real']
 440                         : 0;
 441
 442                 foreach ( $this->mCollated as $fname => $data ) {
 443                         $calls = $data['count'];
 444                         $percent = $total ? 100 * $data['real'] / $total : 0;
 445                         $memory = $data['memory'];
 446                         $prof .= sprintf( $format,
 447                                 substr( $fname, 0, $nameWidth ),
 448                                 $calls,
 449                                 (float)( $data['real'] * 1000 ),
 450                                 (float)( $data['real'] * 1000 ) / $calls,
 451                                 $percent,
 452                                 $memory,
 453                                 ( $data['min_real'] * 1000.0 ),
 454                                 ( $data['max_real'] * 1000.0 ),
 455                                 $data['overhead']
 456                         );
 457                 }
 458                 $prof .= "\nTotal: $total\n\n";
 459
 460                 return $prof;
 461         }
 462
 463         /**
 464          * @return array
 465          */
 466         public function getRawData() {
 467                 // This method is called before shutdown in the footer method on Skins.
 468                 // If some outer methods have not yet called wfProfileOut(), work around
 469                 // that by clearing anything in the work stack to just the "-total" entry.
 470                 // Collate after doing this so the results do not include profile errors.
 471                 if ( count( $this->mWorkStack ) > 1 ) {
 472                         $oldWorkStack = $this->mWorkStack;
 473                         $this->mWorkStack = array( $this->mWorkStack[0] ); // just the "-total" one
 474                 } else {
 475                         $oldWorkStack = null;
 476                 }
 477                 $this->collateData();
 478                 // If this trick is used, then the old work stack is swapped back afterwards
 479                 // and mCollateDone is reset to false. This means that logData() will still
 480                 // make use of all the method data since the missing wfProfileOut() calls
 481                 // should be made by the time it is called.
 482                 if ( $oldWorkStack ) {
 483                         $this->mWorkStack = $oldWorkStack;
 484                         $this->mCollateDone = false;
 485                 }
 486
 487                 $total = isset( $this->mCollated['-total'] )
 488                         ? $this->mCollated['-total']['real']
 489                         : 0;
 490
 491                 $profile = array();
 492                 foreach ( $this->mCollated as $fname => $data ) {
 493                         $periods = array();
 494                         foreach ( $data['periods'] as $period ) {
 495                                 $period['start'] *= 1000;
 496                                 $period['end'] *= 1000;
 497                                 $periods[] = $period;
 498                         }
 499                         $profile[] = array(
 500                                 'name' => $fname,
 501                                 'calls' => $data['count'],
 502                                 'elapsed' => $data['real'] * 1000,
 503                                 'percent' => $total ? 100 * $data['real'] / $total : 0,
 504                                 'memory' => $data['memory'],
 505                                 'min' => $data['min_real'] * 1000,
 506                                 'max' => $data['max_real'] * 1000,
 507                                 'overhead' => $data['overhead'],
 508                                 'periods' => $periods
 509                         );
 510                 }
 511
 512                 return $profile;
 513         }
 514
 515         /**
 516          * Dummy calls to wfProfileIn/wfProfileOut to calculate its overhead
 517          */
 518         protected static function calculateOverhead( $profileCount ) {
 519                 wfProfileIn( '-overhead-total' );
 520                 for ( $i = 0; $i < $profileCount; $i++ ) {
 521                         wfProfileIn( '-overhead-internal' );
 522                         wfProfileOut( '-overhead-internal' );
 523                 }
 524                 wfProfileOut( '-overhead-total' );
 525         }
 526
 527         /**
 528          * Counts the number of profiled function calls sitting under
 529          * the given point in the call graph. Not the most efficient algo.
 530          *
 531          * @param array $stack
 532          * @param int $start
 533          * @return int
 534          */
 535         protected function calltreeCount( $stack, $start ) {
 536                 $level = $stack[$start][1];
 537                 $count = 0;
 538                 for ( $i = $start -1; $i >= 0 && $stack[$i][1] > $level; $i-- ) {
 539                         $count ++;
 540                 }
 541                 return $count;
 542         }
 543
 544         /**
 545          * Get the content type sent out to the client.
 546          * Used for profilers that output instead of store data.
 547          * @return string
 548          */
 549         protected function getContentType() {
 550                 foreach ( headers_list() as $header ) {
 551                         if ( preg_match( '#^content-type: (\w+/\w+);?#i', $header, $m ) ) {
 552                                 return $m[1];
 553                         }
 554                 }
 555                 return null;
 556         }
 557 }