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          * Return whether this a stub profiler
  62          *
  63          * @return bool
  64          */
  65         public function isStub() {
  66                 return false;
  67         }
  68
  69         /**
  70          * Add the inital item in the stack.
  71          */
  72         protected function addInitialStack() {
  73                 $this->errorEntry = $this->getErrorEntry();
  74
  75                 $initialTime = $this->getInitialTime( 'wall' );
  76                 $initialCpu = $this->getInitialTime( 'cpu' );
  77                 if ( $initialTime !== null && $initialCpu !== null ) {
  78                         $this->workStack[] = array( '-total', 0, $initialTime, $initialCpu, 0 );
  79                         if ( $this->collateOnly ) {
  80                                 $this->workStack[] = array( '-setup', 1, $initialTime, $initialCpu, 0 );
  81                                 $this->profileOut( '-setup' );
  82                         } else {
  83                                 $this->stack[] = array( '-setup', 1, $initialTime, $initialCpu, 0,
  84                                         $this->getTime( 'wall' ), $this->getTime( 'cpu' ), 0 );
  85                         }
  86                 } else {
  87                         $this->profileIn( '-total' );
  88                 }
  89         }
  90
  91         /**
  92          * @return array Initial collation entry
  93          */
  94         protected function getZeroEntry() {
  95                 return array(
  96                         'cpu'      => 0.0,
  97                         'cpu_sq'   => 0.0,
  98                         'real'     => 0.0,
  99                         'real_sq'  => 0.0,
 100                         'memory'   => 0,
 101                         'count'    => 0,
 102                         'min_cpu'  => 0.0,
 103                         'max_cpu'  => 0.0,
 104                         'min_real' => 0.0,
 105                         'max_real' => 0.0,
 106                         'periods'  => array(), // not filled if collateOnly
 107                         'overhead' => 0 // not filled if collateOnly
 108                 );
 109         }
 110
 111         /**
 112          * @return array Initial collation entry for errors
 113          */
 114         protected function getErrorEntry() {
 115                 $entry = $this->getZeroEntry();
 116                 $entry['count'] = 1;
 117                 return $entry;
 118         }
 119
 120         /**
 121          * Update the collation entry for a given method name
 122          *
 123          * @param string $name
 124          * @param float $elapsedCpu
 125          * @param float $elapsedReal
 126          * @param int $memChange
 127          * @param int $subcalls
 128          * @param array|null $period Map of ('start','end','memory','subcalls')
 129          */
 130         protected function updateEntry(
 131                 $name, $elapsedCpu, $elapsedReal, $memChange, $subcalls = 0, $period = null
 132         ) {
 133                 $entry =& $this->collated[$name];
 134                 if ( !is_array( $entry ) ) {
 135                         $entry = $this->getZeroEntry();
 136                         $this->collated[$name] =& $entry;
 137                 }
 138                 $entry['cpu'] += $elapsedCpu;
 139                 $entry['cpu_sq'] += $elapsedCpu * $elapsedCpu;
 140                 $entry['real'] += $elapsedReal;
 141                 $entry['real_sq'] += $elapsedReal * $elapsedReal;
 142                 $entry['memory'] += $memChange > 0 ? $memChange : 0;
 143                 $entry['count']++;
 144                 $entry['min_cpu'] = $elapsedCpu < $entry['min_cpu'] ? $elapsedCpu : $entry['min_cpu'];
 145                 $entry['max_cpu'] = $elapsedCpu > $entry['max_cpu'] ? $elapsedCpu : $entry['max_cpu'];
 146                 $entry['min_real'] = $elapsedReal < $entry['min_real'] ? $elapsedReal : $entry['min_real'];
 147                 $entry['max_real'] = $elapsedReal > $entry['max_real'] ? $elapsedReal : $entry['max_real'];
 148                 // Apply optional fields
 149                 $entry['overhead'] += $subcalls;
 150                 if ( $period ) {
 151                         $entry['periods'][] = $period;
 152                 }
 153         }
 154
 155         /**
 156          * Called by wfProfieIn()
 157          *
 158          * @param string $functionname
 159          */
 160         public function profileIn( $functionname ) {
 161                 global $wgDebugFunctionEntry;
 162
 163                 if ( $wgDebugFunctionEntry ) {
 164                         $this->debug( str_repeat( ' ', count( $this->workStack ) ) .
 165                                 'Entering ' . $functionname . "\n" );
 166                 }
 167
 168                 $this->workStack[] = array(
 169                         $functionname,
 170                         count( $this->workStack ),
 171                         $this->getTime( 'time' ),
 172                         $this->getTime( 'cpu' ),
 173                         memory_get_usage()
 174                 );
 175         }
 176
 177         /**
 178          * Called by wfProfieOut()
 179          *
 180          * @param string $functionname
 181          */
 182         public function profileOut( $functionname ) {
 183                 global $wgDebugFunctionEntry;
 184
 185                 if ( $wgDebugFunctionEntry ) {
 186                         $this->debug( str_repeat( ' ', count( $this->workStack ) - 1 ) .
 187                                 'Exiting ' . $functionname . "\n" );
 188                 }
 189
 190                 $item = array_pop( $this->workStack );
 191                 list( $ofname, /* $ocount */, $ortime, $octime, $omem ) = $item;
 192
 193                 if ( $item === null ) {
 194                         $this->debugGroup( 'profileerror', "Profiling error: $functionname" );
 195                 } else {
 196                         if ( $functionname === 'close' ) {
 197                                 if ( $ofname !== '-total' ) {
 198                                         $message = "Profile section ended by close(): {$ofname}";
 199                                         $this->debugGroup( 'profileerror', $message );
 200                                         if ( $this->collateOnly ) {
 201                                                 $this->collated[$message] = $this->errorEntry;
 202                                         } else {
 203                                                 $this->stack[] = array( $message, 0, 0.0, 0.0, 0, 0.0, 0.0, 0 );
 204                                         }
 205                                 }
 206                                 $functionname = $ofname;
 207                         } elseif ( $ofname !== $functionname ) {
 208                                 $message = "Profiling error: in({$ofname}), out($functionname)";
 209                                 $this->debugGroup( 'profileerror', $message );
 210                                 if ( $this->collateOnly ) {
 211                                         $this->collated[$message] = $this->errorEntry;
 212                                 } else {
 213                                         $this->stack[] = array( $message, 0, 0.0, 0.0, 0, 0.0, 0.0, 0 );
 214                                 }
 215                         }
 216                         $realTime = $this->getTime( 'wall' );
 217                         $cpuTime = $this->getTime( 'cpu' );
 218                         if ( $this->collateOnly ) {
 219                                 $elapsedcpu = $cpuTime - $octime;
 220                                 $elapsedreal = $realTime - $ortime;
 221                                 $memchange = memory_get_usage() - $omem;
 222                                 $this->updateEntry( $functionname, $elapsedcpu, $elapsedreal, $memchange );
 223                         } else {
 224                                 $this->stack[] = array_merge( $item,
 225                                         array( $realTime, $cpuTime,     memory_get_usage() ) );
 226                         }
 227                 }
 228         }
 229
 230         public function scopedProfileIn( $section ) {
 231                 $this->profileIn( $section );
 232
 233                 $that = $this;
 234                 return new ScopedCallback( function() use ( $that, $section ) {
 235                         $that->profileOut( $section );
 236                 } );
 237         }
 238
 239         /**
 240          * Close opened profiling sections
 241          */
 242         public function close() {
 243                 while ( count( $this->workStack ) ) {
 244                         $this->profileOut( 'close' );
 245                 }
 246         }
 247
 248         /**
 249          * Returns a profiling output to be stored in debug file
 250          *
 251          * @return string
 252          */
 253         public function getOutput() {
 254                 global $wgDebugFunctionEntry, $wgProfileCallTree;
 255
 256                 $wgDebugFunctionEntry = false; // hack
 257
 258                 if ( !count( $this->stack ) && !count( $this->collated ) ) {
 259                         return "No profiling output\n";
 260                 }
 261
 262                 if ( $wgProfileCallTree ) {
 263                         return $this->getCallTree();
 264                 } else {
 265                         return $this->getFunctionReport();
 266                 }
 267         }
 268
 269         /**
 270          * Returns a tree of function call instead of a list of functions
 271          * @return string
 272          */
 273         protected function getCallTree() {
 274                 return implode( '', array_map(
 275                         array( &$this, 'getCallTreeLine' ), $this->remapCallTree( $this->stack )
 276                 ) );
 277         }
 278
 279         /**
 280          * Recursive function the format the current profiling array into a tree
 281          *
 282          * @param array $stack Profiling array
 283          * @return array
 284          */
 285         protected function remapCallTree( array $stack ) {
 286                 if ( count( $stack ) < 2 ) {
 287                         return $stack;
 288                 }
 289                 $outputs = array();
 290                 for ( $max = count( $stack ) - 1; $max > 0; ) {
 291                         /* Find all items under this entry */
 292                         $level = $stack[$max][1];
 293                         $working = array();
 294                         for ( $i = $max -1; $i >= 0; $i-- ) {
 295                                 if ( $stack[$i][1] > $level ) {
 296                                         $working[] = $stack[$i];
 297                                 } else {
 298                                         break;
 299                                 }
 300                         }
 301                         $working = $this->remapCallTree( array_reverse( $working ) );
 302                         $output = array();
 303                         foreach ( $working as $item ) {
 304                                 array_push( $output, $item );
 305                         }
 306                         array_unshift( $output, $stack[$max] );
 307                         $max = $i;
 308
 309                         array_unshift( $outputs, $output );
 310                 }
 311                 $final = array();
 312                 foreach ( $outputs as $output ) {
 313                         foreach ( $output as $item ) {
 314                                 $final[] = $item;
 315                         }
 316                 }
 317                 return $final;
 318         }
 319
 320         /**
 321          * Callback to get a formatted line for the call tree
 322          * @param array $entry
 323          * @return string
 324          */
 325         protected function getCallTreeLine( $entry ) {
 326                 list( $fname, $level, $startreal, , , $endreal ) = $entry;
 327                 $delta = $endreal - $startreal;
 328                 $space = str_repeat( ' ', $level );
 329                 # The ugly double sprintf is to work around a PHP bug,
 330                 # which has been fixed in recent releases.
 331                 return sprintf( "%10s %s %s\n",
 332                         trim( sprintf( "%7.3f", $delta * 1000.0 ) ), $space, $fname );
 333         }
 334
 335         /**
 336          * Return the collated data, collating first if need be
 337          * @return array
 338          */
 339         public function getCollatedData() {
 340                 if ( !$this->collateDone ) {
 341                         $this->collateData();
 342                 }
 343                 return $this->collated;
 344         }
 345
 346         /**
 347          * Populate collated
 348          */
 349         protected function collateData() {
 350                 if ( $this->collateDone ) {
 351                         return;
 352                 }
 353                 $this->collateDone = true;
 354                 $this->close(); // set "-total" entry
 355
 356                 if ( $this->collateOnly ) {
 357                         return; // already collated as methods exited
 358                 }
 359
 360                 $this->collated = array();
 361
 362                 # Estimate profiling overhead
 363                 $profileCount = count( $this->stack );
 364                 self::calculateOverhead( $profileCount );
 365
 366                 # First, subtract the overhead!
 367                 $overheadTotal = $overheadMemory = $overheadInternal = array();
 368                 foreach ( $this->stack as $entry ) {
 369                         // $entry is (name,pos,rtime0,cputime0,mem0,rtime1,cputime1,mem1)
 370                         $fname = $entry[0];
 371                         $elapsed = $entry[5] - $entry[2];
 372                         $memchange = $entry[7] - $entry[4];
 373
 374                         if ( $fname === '-overhead-total' ) {
 375                                 $overheadTotal[] = $elapsed;
 376                                 $overheadMemory[] = max( 0, $memchange );
 377                         } elseif ( $fname === '-overhead-internal' ) {
 378                                 $overheadInternal[] = $elapsed;
 379                         }
 380                 }
 381                 $overheadTotal = $overheadTotal ?
 382                         array_sum( $overheadTotal ) / count( $overheadInternal ) : 0;
 383                 $overheadMemory = $overheadMemory ?
 384                         array_sum( $overheadMemory ) / count( $overheadInternal ) : 0;
 385                 $overheadInternal = $overheadInternal ?
 386                         array_sum( $overheadInternal ) / count( $overheadInternal ) : 0;
 387
 388                 # Collate
 389                 foreach ( $this->stack as $index => $entry ) {
 390                         // $entry is (name,pos,rtime0,cputime0,mem0,rtime1,cputime1,mem1)
 391                         $fname = $entry[0];
 392                         $elapsedCpu = $entry[6] - $entry[3];
 393                         $elapsedReal = $entry[5] - $entry[2];
 394                         $memchange = $entry[7] - $entry[4];
 395                         $subcalls = $this->calltreeCount( $this->stack, $index );
 396
 397                         if ( substr( $fname, 0, 9 ) !== '-overhead' ) {
 398                                 # Adjust for profiling overhead (except special values with elapsed=0
 399                                 if ( $elapsed ) {
 400                                         $elapsed -= $overheadInternal;
 401                                         $elapsed -= ( $subcalls * $overheadTotal );
 402                                         $memchange -= ( $subcalls * $overheadMemory );
 403                                 }
 404                         }
 405
 406                         $period = array( 'start' => $entry[2], 'end' => $entry[5],
 407                                 'memory' => $memchange, 'subcalls' => $subcalls );
 408                         $this->updateEntry( $fname, $elapsedCpu, $elapsedReal, $memchange, $subcalls, $period );
 409                 }
 410
 411                 $this->collated['-overhead-total']['count'] = $profileCount;
 412                 arsort( $this->collated, SORT_NUMERIC );
 413         }
 414
 415         /**
 416          * Returns a list of profiled functions.
 417          *
 418          * @return string
 419          */
 420         protected function getFunctionReport() {
 421                 $this->collateData();
 422
 423                 $width = 140;
 424                 $nameWidth = $width - 65;
 425                 $format = "%-{$nameWidth}s %6d %13.3f %13.3f %13.3f%% %9d  (%13.3f -%13.3f) [%d]\n";
 426                 $titleFormat = "%-{$nameWidth}s %6s %13s %13s %13s %9s\n";
 427                 $prof = "\nProfiling data\n";
 428                 $prof .= sprintf( $titleFormat, 'Name', 'Calls', 'Total', 'Each', '%', 'Mem' );
 429
 430                 $total = isset( $this->collated['-total'] )
 431                         ? $this->collated['-total']['real']
 432                         : 0;
 433
 434                 foreach ( $this->collated as $fname => $data ) {
 435                         $calls = $data['count'];
 436                         $percent = $total ? 100 * $data['real'] / $total : 0;
 437                         $memory = $data['memory'];
 438                         $prof .= sprintf( $format,
 439                                 substr( $fname, 0, $nameWidth ),
 440                                 $calls,
 441                                 (float)( $data['real'] * 1000 ),
 442                                 (float)( $data['real'] * 1000 ) / $calls,
 443                                 $percent,
 444                                 $memory,
 445                                 ( $data['min_real'] * 1000.0 ),
 446                                 ( $data['max_real'] * 1000.0 ),
 447                                 $data['overhead']
 448                         );
 449                 }
 450                 $prof .= "\nTotal: $total\n\n";
 451
 452                 return $prof;
 453         }
 454
 455         public function getFunctionStats() {
 456                 // This method is called before shutdown in the footer method on Skins.
 457                 // If some outer methods have not yet called wfProfileOut(), work around
 458                 // that by clearing anything in the work stack to just the "-total" entry.
 459                 // Collate after doing this so the results do not include profile errors.
 460                 if ( count( $this->workStack ) > 1 ) {
 461                         $oldWorkStack = $this->workStack;
 462                         $this->workStack = array( $this->workStack[0] ); // just the "-total" one
 463                 } else {
 464                         $oldWorkStack = null;
 465                 }
 466                 $this->collateData();
 467                 // If this trick is used, then the old work stack is swapped back afterwards
 468                 // and collateDone is reset to false. This means that logData() will still
 469                 // make use of all the method data since the missing wfProfileOut() calls
 470                 // should be made by the time it is called.
 471                 if ( $oldWorkStack ) {
 472                         $this->workStack = $oldWorkStack;
 473                         $this->collateDone = false;
 474                 }
 475
 476                 $totalCpu = isset( $this->collated['-total'] )
 477                         ? $this->collated['-total']['cpu']
 478                         : 0;
 479                 $totalReal = isset( $this->collated['-total'] )
 480                         ? $this->collated['-total']['real']
 481                         : 0;
 482                 $totalMem = isset( $this->collated['-total'] )
 483                         ? $this->collated['-total']['memory']
 484                         : 0;
 485
 486                 $profile = array();
 487                 foreach ( $this->collated as $fname => $data ) {
 488                         $profile[] = array(
 489                                 'name' => $fname,
 490                                 'calls' => $data['count'],
 491                                 'real' => $data['real'] * 1000,
 492                                 '%real' => $totalReal ? 100 * $data['real'] / $totalReal : 0,
 493                                 'cpu' => $data['cpu'] * 1000,
 494                                 '%cpu' => $totalCpu ? 100 * $data['cpu'] / $totalCpu : 0,
 495                                 'memory' => $data['memory'],
 496                                 '%memory' => $totalMem ? 100 * $data['memory'] / $totalMem : 0,
 497                                 'min' => $data['min_real'] * 1000,
 498                                 'max' => $data['max_real'] * 1000
 499                         );
 500                 }
 501
 502                 return $profile;
 503         }
 504
 505         /**
 506          * Dummy calls to wfProfileIn/wfProfileOut to calculate its overhead
 507          * @param int $profileCount
 508          */
 509         protected static function calculateOverhead( $profileCount ) {
 510                 wfProfileIn( '-overhead-total' );
 511                 for ( $i = 0; $i < $profileCount; $i++ ) {
 512                         wfProfileIn( '-overhead-internal' );
 513                         wfProfileOut( '-overhead-internal' );
 514                 }
 515                 wfProfileOut( '-overhead-total' );
 516         }
 517
 518         /**
 519          * Counts the number of profiled function calls sitting under
 520          * the given point in the call graph. Not the most efficient algo.
 521          *
 522          * @param array $stack
 523          * @param int $start
 524          * @return int
 525          */
 526         protected function calltreeCount( $stack, $start ) {
 527                 $level = $stack[$start][1];
 528                 $count = 0;
 529                 for ( $i = $start -1; $i >= 0 && $stack[$i][1] > $level; $i-- ) {
 530                         $count ++;
 531                 }
 532                 return $count;
 533         }
 534
 535         /**
 536          * Get the initial time of the request, based either on $wgRequestTime or
 537          * $wgRUstart. Will return null if not able to find data.
 538          *
 539          * @param string|bool $metric Metric to use, with the following possibilities:
 540          *   - user: User CPU time (without system calls)
 541          *   - cpu: Total CPU time (user and system calls)
 542          *   - wall (or any other string): elapsed time
 543          *   - false (default): will fall back to default metric
 544          * @return float|null
 545          */
 546         protected function getTime( $metric = 'wall' ) {
 547                 if ( $metric === 'cpu' || $metric === 'user' ) {
 548                         $ru = wfGetRusage();
 549                         if ( !$ru ) {
 550                                 return 0;
 551                         }
 552                         $time = $ru['ru_utime.tv_sec'] + $ru['ru_utime.tv_usec'] / 1e6;
 553                         if ( $metric === 'cpu' ) {
 554                                 # This is the time of system calls, added to the user time
 555                                 # it gives the total CPU time
 556                                 $time += $ru['ru_stime.tv_sec'] + $ru['ru_stime.tv_usec'] / 1e6;
 557                         }
 558                         return $time;
 559                 } else {
 560                         return microtime( true );
 561                 }
 562         }
 563
 564         /**
 565          * Get the initial time of the request, based either on $wgRequestTime or
 566          * $wgRUstart. Will return null if not able to find data.
 567          *
 568          * @param string|bool $metric Metric to use, with the following possibilities:
 569          *   - user: User CPU time (without system calls)
 570          *   - cpu: Total CPU time (user and system calls)
 571          *   - wall (or any other string): elapsed time
 572          *   - false (default): will fall back to default metric
 573          * @return float|null
 574          */
 575         protected function getInitialTime( $metric = 'wall' ) {
 576                 global $wgRequestTime, $wgRUstart;
 577
 578                 if ( $metric === 'cpu' || $metric === 'user' ) {
 579                         if ( !count( $wgRUstart ) ) {
 580                                 return null;
 581                         }
 582
 583                         $time = $wgRUstart['ru_utime.tv_sec'] + $wgRUstart['ru_utime.tv_usec'] / 1e6;
 584                         if ( $metric === 'cpu' ) {
 585                                 # This is the time of system calls, added to the user time
 586                                 # it gives the total CPU time
 587                                 $time += $wgRUstart['ru_stime.tv_sec'] + $wgRUstart['ru_stime.tv_usec'] / 1e6;
 588                         }
 589                         return $time;
 590                 } else {
 591                         if ( empty( $wgRequestTime ) ) {
 592                                 return null;
 593                         } else {
 594                                 return $wgRequestTime;
 595                         }
 596                 }
 597         }
 598
 599         /**
 600          * Add an entry in the debug log file
 601          *
 602          * @param string $s String to output
 603          */
 604         protected function debug( $s ) {
 605                 if ( function_exists( 'wfDebug' ) ) {
 606                         wfDebug( $s );
 607                 }
 608         }
 609
 610         /**
 611          * Add an entry in the debug log group
 612          *
 613          * @param string $group Group to send the message to
 614          * @param string $s String to output
 615          */
 616         protected function debugGroup( $group, $s ) {
 617                 if ( function_exists( 'wfDebugLog' ) ) {
 618                         wfDebugLog( $group, $s );
 619                 }
 620         }
 621 }