3 * Arbitrary section name based PHP profiling.
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.
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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.
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
22 * @author Aaron Schulz
26 * Custom PHP profiler for parser/DB type section names that xhprof/xdebug can't handle
30 class SectionProfiler
{
31 /** @var array Map of (mem,real,cpu) */
33 /** @var array Map of (mem,real,cpu) */
35 /** @var array List of resolved profile calls with start/end data */
36 protected $stack = array();
37 /** @var array Queue of open profile calls with start data */
38 protected $workStack = array();
40 /** @var array Map of (function name => aggregate data array) */
41 protected $collated = array();
43 protected $collateDone = false;
45 /** @var bool Whether to collect the full stack trace or just aggregates */
46 protected $collateOnly = true;
47 /** @var array Cache of a standard broken collation entry */
48 protected $errorEntry;
49 /** @var callable Cache of a profile out callback */
50 protected $profileOutCallback;
53 * @param array $params
55 public function __construct( array $params = array() ) {
56 $this->errorEntry
= $this->getErrorEntry();
57 $this->collateOnly
= empty( $params['trace'] );
58 $this->profileOutCallback
= function ( $profiler, $section ) {
59 $profiler->profileOutInternal( $section );
64 * @param string $section
65 * @return ScopedCallback
67 public function scopedProfileIn( $section ) {
68 $this->profileInInternal( $section );
71 return new ScopedCallback( $this->profileOutCallback
, array( $that, $section ) );
75 * @param ScopedCallback $section
77 public function scopedProfileOut( ScopedCallback
&$section ) {
82 * Get the aggregated inclusive profiling data for each method
84 * The percent time for each time is based on the current "total" time
85 * used is based on all methods so far. This method can therefore be
86 * called several times in between several profiling calls without the
87 * delays in usage of the profiler skewing the results. A "-total" entry
88 * is always included in the results.
90 * @return array List of method entries arrays, each having:
91 * - name : method name
92 * - calls : the number of invoking calls
93 * - real : real time ellapsed (ms)
94 * - %real : percent real time
95 * - cpu : real time ellapsed (ms)
96 * - %cpu : percent real time
97 * - memory : memory used (bytes)
98 * - %memory : percent memory used
99 * - min_real : min real time in a call (ms)
100 * - max_real : max real time in a call (ms)
102 public function getFunctionStats() {
103 $this->collateData();
105 $totalCpu = max( $this->end
['cpu'] - $this->start
['cpu'], 0 );
106 $totalReal = max( $this->end
['real'] - $this->start
['real'], 0 );
107 $totalMem = max( $this->end
['memory'] - $this->start
['memory'], 0 );
110 foreach ( $this->collated
as $fname => $data ) {
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']
128 'real' => 1000 * $totalReal,
130 'cpu' => 1000 * $totalCpu,
132 'memory' => $totalMem,
134 'min_real' => 1000 * $totalReal,
135 'max_real' => 1000 * $totalReal
142 * Clear all of the profiling data for another run
144 public function reset() {
147 $this->stack
= array();
148 $this->workStack
= array();
149 $this->collated
= array();
150 $this->collateDone
= false;
154 * @return array Initial collation entry
156 protected function getZeroEntry() {
168 * @return array Initial collation entry for errors
170 protected function getErrorEntry() {
171 $entry = $this->getZeroEntry();
177 * Update the collation entry for a given method name
179 * @param string $name
180 * @param float $elapsedCpu
181 * @param float $elapsedReal
182 * @param int $memChange
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;
190 $entry['cpu'] +
= $elapsedCpu;
191 $entry['real'] +
= $elapsedReal;
192 $entry['memory'] +
= $memChange > 0 ?
$memChange : 0;
194 $entry['min_real'] = min( $entry['min_real'], $elapsedReal );
195 $entry['max_real'] = max( $entry['max_real'], $elapsedReal );
199 * This method should not be called outside SectionProfiler
201 * @param string $functionname
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;
209 $cpu = $this->getTime( 'cpu' );
210 $real = $this->getTime( 'wall' );
211 $memory = memory_get_usage();
213 if ( $this->start
=== null ) {
214 $this->start
= array( 'cpu' => $cpu, 'real' => $real, 'memory' => $memory );
217 $this->workStack
[] = array(
219 count( $this->workStack
),
227 * This method should not be called outside SectionProfiler
229 * @param string $functionname
231 public function profileOutInternal( $functionname ) {
232 $item = array_pop( $this->workStack
);
233 if ( $item === null ) {
234 $this->debugGroup( 'profileerror', "Profiling error: $functionname" );
237 list( $ofname, /* $ocount */, $ortime, $octime, $omem ) = $item;
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
;
245 $this->stack
[] = array( $message, 0, 0.0, 0.0, 0, 0.0, 0.0, 0 );
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
;
254 $this->stack
[] = array( $message, 0, 0.0, 0.0, 0, 0.0, 0.0, 0 );
258 $realTime = $this->getTime( 'wall' );
259 $cpuTime = $this->getTime( 'cpu' );
260 $memUsage = memory_get_usage();
262 if ( $this->collateOnly
) {
263 $elapsedcpu = $cpuTime - $octime;
264 $elapsedreal = $realTime - $ortime;
265 $memchange = $memUsage - $omem;
266 $this->updateEntry( $functionname, $elapsedcpu, $elapsedreal, $memchange );
268 $this->stack
[] = array_merge( $item, array( $realTime, $cpuTime, $memUsage ) );
274 'memory' => $memUsage
279 * Returns a tree of function calls with their real times
282 public function getCallTreeReport() {
283 if ( $this->collateOnly
) {
284 throw new Exception( "Tree is only available for trace profiling." );
286 return implode( '', array_map(
287 array( $this, 'getCallTreeLine' ), $this->remapCallTree( $this->stack
)
292 * Recursive function the format the current profiling array into a tree
294 * @param array $stack Profiling array
297 protected function remapCallTree( array $stack ) {
298 if ( count( $stack ) < 2 ) {
302 for ( $max = count( $stack ) - 1; $max > 0; ) {
303 /* Find all items under this entry */
304 $level = $stack[$max][1];
306 for ( $i = $max -1; $i >= 0; $i-- ) {
307 if ( $stack[$i][1] > $level ) {
308 $working[] = $stack[$i];
313 $working = $this->remapCallTree( array_reverse( $working ) );
315 foreach ( $working as $item ) {
316 array_push( $output, $item );
318 array_unshift( $output, $stack[$max] );
321 array_unshift( $outputs, $output );
324 foreach ( $outputs as $output ) {
325 foreach ( $output as $item ) {
333 * Callback to get a formatted line for the call tree
334 * @param array $entry
337 protected function getCallTreeLine( $entry ) {
338 // $entry has (name, level, stime, scpu, smem, etime, ecpu, emem)
339 list( $fname, $level, $startreal, , , $endreal ) = $entry;
340 $delta = $endreal - $startreal;
341 $space = str_repeat( ' ', $level );
342 # The ugly double sprintf is to work around a PHP bug,
343 # which has been fixed in recent releases.
344 return sprintf( "%10s %s %s\n",
345 trim( sprintf( "%7.3f", $delta * 1000.0 ) ), $space, $fname );
349 * Populate collated data
351 protected function collateData() {
352 if ( $this->collateDone
) {
355 $this->collateDone
= true;
356 // Close opened profiling sections
357 while ( count( $this->workStack
) ) {
358 $this->profileOutInternal( 'close' );
361 if ( $this->collateOnly
) {
362 return; // already collated as methods exited
365 $this->collated
= array();
367 # Estimate profiling overhead
368 $oldEnd = $this->end
;
369 $profileCount = count( $this->stack
);
370 $this->calculateOverhead( $profileCount );
372 # First, subtract the overhead!
373 $overheadTotal = $overheadMemory = $overheadInternal = array();
374 foreach ( $this->stack
as $entry ) {
375 // $entry is (name,pos,rtime0,cputime0,mem0,rtime1,cputime1,mem1)
377 $elapsed = $entry[5] - $entry[2];
378 $memchange = $entry[7] - $entry[4];
380 if ( $fname === '-overhead-total' ) {
381 $overheadTotal[] = $elapsed;
382 $overheadMemory[] = max( 0, $memchange );
383 } elseif ( $fname === '-overhead-internal' ) {
384 $overheadInternal[] = $elapsed;
387 $overheadTotal = $overheadTotal ?
388 array_sum( $overheadTotal ) / count( $overheadInternal ) : 0;
389 $overheadMemory = $overheadMemory ?
390 array_sum( $overheadMemory ) / count( $overheadInternal ) : 0;
391 $overheadInternal = $overheadInternal ?
392 array_sum( $overheadInternal ) / count( $overheadInternal ) : 0;
395 foreach ( $this->stack
as $index => $entry ) {
396 // $entry is (name,pos,rtime0,cputime0,mem0,rtime1,cputime1,mem1)
398 $elapsedCpu = $entry[6] - $entry[3];
399 $elapsedReal = $entry[5] - $entry[2];
400 $memchange = $entry[7] - $entry[4];
401 $subcalls = $this->calltreeCount( $this->stack
, $index );
403 if ( substr( $fname, 0, 9 ) !== '-overhead' ) {
404 # Adjust for profiling overhead (except special values with elapsed=0)
406 $elapsed -= $overheadInternal;
407 $elapsed -= ( $subcalls * $overheadTotal );
408 $memchange -= ( $subcalls * $overheadMemory );
412 $this->updateEntry( $fname, $elapsedCpu, $elapsedReal, $memchange );
415 $this->collated
['-overhead-total']['count'] = $profileCount;
416 arsort( $this->collated
, SORT_NUMERIC
);
418 // Unclobber the end info map (the overhead checking alters it)
419 $this->end
= $oldEnd;
423 * Dummy calls to calculate profiling overhead
425 * @param int $profileCount
427 protected function calculateOverhead( $profileCount ) {
428 $this->profileInInternal( '-overhead-total' );
429 for ( $i = 0; $i < $profileCount; $i++
) {
430 $this->profileInInternal( '-overhead-internal' );
431 $this->profileOutInternal( '-overhead-internal' );
433 $this->profileOutInternal( '-overhead-total' );
437 * Counts the number of profiled function calls sitting under
438 * the given point in the call graph. Not the most efficient algo.
440 * @param array $stack
444 protected function calltreeCount( $stack, $start ) {
445 $level = $stack[$start][1];
447 for ( $i = $start -1; $i >= 0 && $stack[$i][1] > $level; $i-- ) {
454 * Get the initial time of the request, based either on $wgRequestTime or
455 * $wgRUstart. Will return null if not able to find data.
457 * @param string|bool $metric Metric to use, with the following possibilities:
458 * - user: User CPU time (without system calls)
459 * - cpu: Total CPU time (user and system calls)
460 * - wall (or any other string): elapsed time
461 * - false (default): will fall back to default metric
464 protected function getTime( $metric = 'wall' ) {
465 if ( $metric === 'cpu' ||
$metric === 'user' ) {
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
;
478 return microtime( true );
483 * Add an entry in the debug log file
485 * @param string $s String to output
487 protected function debug( $s ) {
488 if ( function_exists( 'wfDebug' ) ) {
494 * Add an entry in the debug log group
496 * @param string $group Group to send the message to
497 * @param string $s String to output
499 protected function debugGroup( $group, $s ) {
500 if ( function_exists( 'wfDebugLog' ) ) {
501 wfDebugLog( $group, $s );