MediaWiki REL1_34
SectionProfiler.php
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1<?php
23use Wikimedia\ScopedCallback;
24
32 protected $start;
34 protected $end;
36 protected $stack = [];
38 protected $workStack = [];
39
41 protected $collated = [];
43 protected $collateDone = false;
44
46 protected $collateOnly = true;
48 protected $errorEntry;
49
53 public function __construct( array $params = [] ) {
54 $this->errorEntry = $this->getErrorEntry();
55 $this->collateOnly = empty( $params['trace'] );
56 }
57
62 public function scopedProfileIn( $section ) {
63 $this->profileInInternal( $section );
64
65 return new SectionProfileCallback( $this, $section );
66 }
67
71 public function scopedProfileOut( ScopedCallback &$section ) {
72 $section = null;
73 }
74
96 public function getFunctionStats() {
97 $this->collateData();
98
99 if ( is_array( $this->start ) ) {
100 $totalCpu = max( $this->end['cpu'] - $this->start['cpu'], 0 );
101 $totalReal = max( $this->end['real'] - $this->start['real'], 0 );
102 $totalMem = max( $this->end['memory'] - $this->start['memory'], 0 );
103 } else {
104 $totalCpu = 0;
105 $totalReal = 0;
106 $totalMem = 0;
107 }
108
109 $profile = [];
110 foreach ( $this->collated as $fname => $data ) {
111 $profile[] = [
112 'name' => $fname,
113 'calls' => $data['count'],
114 'real' => $data['real'] * 1000,
115 '%real' => $totalReal ? 100 * $data['real'] / $totalReal : 0,
116 'cpu' => $data['cpu'] * 1000,
117 '%cpu' => $totalCpu ? 100 * $data['cpu'] / $totalCpu : 0,
118 'memory' => $data['memory'],
119 '%memory' => $totalMem ? 100 * $data['memory'] / $totalMem : 0,
120 'min_real' => 1000 * $data['min_real'],
121 'max_real' => 1000 * $data['max_real']
122 ];
123 }
124
125 $profile[] = [
126 'name' => '-total',
127 'calls' => 1,
128 'real' => 1000 * $totalReal,
129 '%real' => 100,
130 'cpu' => 1000 * $totalCpu,
131 '%cpu' => 100,
132 'memory' => $totalMem,
133 '%memory' => 100,
134 'min_real' => 1000 * $totalReal,
135 'max_real' => 1000 * $totalReal
136 ];
137
138 return $profile;
139 }
140
144 public function reset() {
145 $this->start = null;
146 $this->end = null;
147 $this->stack = [];
148 $this->workStack = [];
149 $this->collated = [];
150 $this->collateDone = false;
151 }
152
156 protected function getZeroEntry() {
157 return [
158 'cpu' => 0.0,
159 'real' => 0.0,
160 'memory' => 0,
161 'count' => 0,
162 'min_real' => 0.0,
163 'max_real' => 0.0
164 ];
165 }
166
170 protected function getErrorEntry() {
171 $entry = $this->getZeroEntry();
172 $entry['count'] = 1;
173 return $entry;
174 }
175
184 protected function updateEntry( $name, $elapsedCpu, $elapsedReal, $memChange ) {
185 $entry =& $this->collated[$name];
186 if ( !is_array( $entry ) ) {
187 $entry = $this->getZeroEntry();
188 $this->collated[$name] =& $entry;
189 }
190 $entry['cpu'] += $elapsedCpu;
191 $entry['real'] += $elapsedReal;
192 $entry['memory'] += $memChange > 0 ? $memChange : 0;
193 $entry['count']++;
194 $entry['min_real'] = min( $entry['min_real'], $elapsedReal );
195 $entry['max_real'] = max( $entry['max_real'], $elapsedReal );
196 }
197
203 public function profileInInternal( $functionname ) {
204 // Once the data is collated for reports, any future calls
205 // should clear the collation cache so the next report will
206 // reflect them. This matters when trace mode is used.
207 $this->collateDone = false;
208
209 $cpu = $this->getTime( 'cpu' );
210 $real = $this->getTime( 'wall' );
211 $memory = memory_get_usage();
212
213 if ( $this->start === null ) {
214 $this->start = [ 'cpu' => $cpu, 'real' => $real, 'memory' => $memory ];
215 }
216
217 $this->workStack[] = [
218 $functionname,
219 count( $this->workStack ),
220 $real,
221 $cpu,
222 $memory
223 ];
224 }
225
231 public function profileOutInternal( $functionname ) {
232 $item = array_pop( $this->workStack );
233 if ( $item === null ) {
234 $this->debugGroup( 'profileerror', "Profiling error: $functionname" );
235 return;
236 }
237 list( $ofname, /* $ocount */, $ortime, $octime, $omem ) = $item;
238
239 if ( $functionname === 'close' ) {
240 $message = "Profile section ended by close(): {$ofname}";
241 $this->debugGroup( 'profileerror', $message );
242 if ( $this->collateOnly ) {
243 $this->collated[$message] = $this->errorEntry;
244 } else {
245 $this->stack[] = [ $message, 0, 0.0, 0.0, 0, 0.0, 0.0, 0 ];
246 }
247 $functionname = $ofname;
248 } elseif ( $ofname !== $functionname ) {
249 $message = "Profiling error: in({$ofname}), out($functionname)";
250 $this->debugGroup( 'profileerror', $message );
251 if ( $this->collateOnly ) {
252 $this->collated[$message] = $this->errorEntry;
253 } else {
254 $this->stack[] = [ $message, 0, 0.0, 0.0, 0, 0.0, 0.0, 0 ];
255 }
256 }
257
258 $realTime = $this->getTime( 'wall' );
259 $cpuTime = $this->getTime( 'cpu' );
260 $memUsage = memory_get_usage();
261
262 if ( $this->collateOnly ) {
263 $elapsedcpu = $cpuTime - $octime;
264 $elapsedreal = $realTime - $ortime;
265 $memchange = $memUsage - $omem;
266 $this->updateEntry( $functionname, $elapsedcpu, $elapsedreal, $memchange );
267 } else {
268 $this->stack[] = array_merge( $item, [ $realTime, $cpuTime, $memUsage ] );
269 }
270
271 $this->end = [
272 'cpu' => $cpuTime,
273 'real' => $realTime,
274 'memory' => $memUsage
275 ];
276 }
277
283 public function getCallTreeReport() {
284 if ( $this->collateOnly ) {
285 throw new Exception( "Tree is only available for trace profiling." );
286 }
287 return implode( '', array_map(
288 [ $this, 'getCallTreeLine' ], $this->remapCallTree( $this->stack )
289 ) );
290 }
291
298 protected function remapCallTree( array $stack ) {
299 if ( count( $stack ) < 2 ) {
300 return $stack;
301 }
302 $outputs = [];
303 for ( $max = count( $stack ) - 1; $max > 0; ) {
304 /* Find all items under this entry */
305 $level = $stack[$max][1];
306 $working = [];
307 for ( $i = $max - 1; $i >= 0; $i-- ) {
308 if ( $stack[$i][1] > $level ) {
309 $working[] = $stack[$i];
310 } else {
311 break;
312 }
313 }
314 $working = $this->remapCallTree( array_reverse( $working ) );
315 $output = [];
316 foreach ( $working as $item ) {
317 array_push( $output, $item );
318 }
319 array_unshift( $output, $stack[$max] );
320 $max = $i;
321
322 array_unshift( $outputs, $output );
323 }
324 $final = [];
325 foreach ( $outputs as $output ) {
326 foreach ( $output as $item ) {
327 $final[] = $item;
328 }
329 }
330 return $final;
331 }
332
338 protected function getCallTreeLine( $entry ) {
339 // $entry has (name, level, stime, scpu, smem, etime, ecpu, emem)
340 list( $fname, $level, $startreal, , , $endreal ) = $entry;
341 $delta = $endreal - $startreal;
342 $space = str_repeat( ' ', $level );
343 # The ugly double sprintf is to work around a PHP bug,
344 # which has been fixed in recent releases.
345 return sprintf( "%10s %s %s\n",
346 trim( sprintf( "%7.3f", $delta * 1000.0 ) ), $space, $fname );
347 }
348
352 protected function collateData() {
353 if ( $this->collateDone ) {
354 return;
355 }
356 $this->collateDone = true;
357 // Close opened profiling sections
358 while ( count( $this->workStack ) ) {
359 $this->profileOutInternal( 'close' );
360 }
361
362 if ( $this->collateOnly ) {
363 return; // already collated as methods exited
364 }
365
366 $this->collated = [];
367
368 # Estimate profiling overhead
369 $oldEnd = $this->end;
370 $profileCount = count( $this->stack );
371 $this->calculateOverhead( $profileCount );
372
373 # First, subtract the overhead!
374 $overheadTotal = $overheadMemory = $overheadInternal = [];
375 foreach ( $this->stack as $entry ) {
376 // $entry is (name,pos,rtime0,cputime0,mem0,rtime1,cputime1,mem1)
377 $fname = $entry[0];
378 $elapsed = $entry[5] - $entry[2];
379 $memchange = $entry[7] - $entry[4];
380
381 if ( $fname === '-overhead-total' ) {
382 $overheadTotal[] = $elapsed;
383 $overheadMemory[] = max( 0, $memchange );
384 } elseif ( $fname === '-overhead-internal' ) {
385 $overheadInternal[] = $elapsed;
386 }
387 }
388 $overheadTotal = $overheadTotal ?
389 array_sum( $overheadTotal ) / count( $overheadInternal ) : 0;
390 $overheadMemory = $overheadMemory ?
391 array_sum( $overheadMemory ) / count( $overheadInternal ) : 0;
392 $overheadInternal = $overheadInternal ?
393 array_sum( $overheadInternal ) / count( $overheadInternal ) : 0;
394
395 # Collate
396 foreach ( $this->stack as $index => $entry ) {
397 // $entry is (name,pos,rtime0,cputime0,mem0,rtime1,cputime1,mem1)
398 $fname = $entry[0];
399 $elapsedCpu = $entry[6] - $entry[3];
400 $elapsedReal = $entry[5] - $entry[2];
401 $memchange = $entry[7] - $entry[4];
402 $subcalls = $this->calltreeCount( $this->stack, $index );
403
404 if ( substr( $fname, 0, 9 ) !== '-overhead' ) {
405 # Adjust for profiling overhead (except special values with elapsed=0)
406 if ( $elapsed ) {
407 $elapsed -= $overheadInternal;
408 $elapsed -= ( $subcalls * $overheadTotal );
409 $memchange -= ( $subcalls * $overheadMemory );
410 }
411 }
412
413 $this->updateEntry( $fname, $elapsedCpu, $elapsedReal, $memchange );
414 }
415
416 $this->collated['-overhead-total']['count'] = $profileCount;
417 arsort( $this->collated, SORT_NUMERIC );
418
419 // Unclobber the end info map (the overhead checking alters it)
420 $this->end = $oldEnd;
421 }
422
428 protected function calculateOverhead( $profileCount ) {
429 $this->profileInInternal( '-overhead-total' );
430 for ( $i = 0; $i < $profileCount; $i++ ) {
431 $this->profileInInternal( '-overhead-internal' );
432 $this->profileOutInternal( '-overhead-internal' );
433 }
434 $this->profileOutInternal( '-overhead-total' );
435 }
436
445 protected function calltreeCount( $stack, $start ) {
446 $level = $stack[$start][1];
447 $count = 0;
448 for ( $i = $start - 1; $i >= 0 && $stack[$i][1] > $level; $i-- ) {
449 $count++;
450 }
451 return $count;
452 }
453
464 protected function getTime( $metric = 'wall' ) {
465 if ( $metric === 'cpu' || $metric === 'user' ) {
466 $ru = wfGetRusage();
467 if ( !$ru ) {
468 return 0;
469 }
470 $time = $ru['ru_utime.tv_sec'] + $ru['ru_utime.tv_usec'] / 1e6;
471 if ( $metric === 'cpu' ) {
472 # This is the time of system calls, added to the user time
473 # it gives the total CPU time
474 $time += $ru['ru_stime.tv_sec'] + $ru['ru_stime.tv_usec'] / 1e6;
475 }
476 return $time;
477 } else {
478 return microtime( true );
479 }
480 }
481
487 protected function debug( $s ) {
488 if ( function_exists( 'wfDebug' ) ) {
489 wfDebug( $s );
490 }
491 }
492
499 protected function debugGroup( $group, $s ) {
500 if ( function_exists( 'wfDebugLog' ) ) {
501 wfDebugLog( $group, $s );
502 }
503 }
504}
wfDebug( $text, $dest='all', array $context=[])
Sends a line to the debug log if enabled or, optionally, to a comment in output.
wfGetRusage()
Get system resource usage of current request context.
wfDebugLog( $logGroup, $text, $dest='all', array $context=[])
Send a line to a supplementary debug log file, if configured, or main debug log if not.
Subclass ScopedCallback to avoid call_user_func_array(), which is slow.
Custom PHP profiler for parser/DB type section names that xhprof/xdebug can't handle.
array $stack
List of resolved profile calls with start/end data.
remapCallTree(array $stack)
Recursive function the format the current profiling array into a tree.
getCallTreeLine( $entry)
Callback to get a formatted line for the call tree.
profileInInternal( $functionname)
This method should not be called outside SectionProfiler.
array $errorEntry
Cache of a standard broken collation entry.
scopedProfileOut(ScopedCallback &$section)
array $collated
Map of (function name => aggregate data array)
debug( $s)
Add an entry in the debug log file.
getTime( $metric='wall')
Get the initial time of the request, based on getrusage()
bool $collateOnly
Whether to collect the full stack trace or just aggregates.
__construct(array $params=[])
array $workStack
Queue of open profile calls with start data.
array $start
Map of (mem,real,cpu)
debugGroup( $group, $s)
Add an entry in the debug log group.
getFunctionStats()
Get the aggregated inclusive profiling data for each method.
getCallTreeReport()
Returns a tree of function calls with their real times.
scopedProfileIn( $section)
calculateOverhead( $profileCount)
Dummy calls to calculate profiling overhead.
profileOutInternal( $functionname)
This method should not be called outside SectionProfiler.
reset()
Clear all of the profiling data for another run.
updateEntry( $name, $elapsedCpu, $elapsedReal, $memChange)
Update the collation entry for a given method name.
array $end
Map of (mem,real,cpu)
calltreeCount( $stack, $start)
Counts the number of profiled function calls sitting under the given point in the call graph.
collateData()
Populate collated data.