includes/profiler/ProfilerMwprof.php

   1 <?php
   2 /**
   3  * Profiler class for Mwprof.
   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  * Profiler class for Mwprof.
  26  *
  27  * Mwprof is a high-performance MediaWiki profiling data collector, designed to
  28  * collect profiling data from multiple hosts running in tandem. This class
  29  * serializes profiling samples into MessagePack arrays and sends them to an
  30  * Mwprof instance via UDP.
  31  *
  32  * @see https://github.com/wikimedia/operations-software-mwprof
  33  * @since 1.23
  34  */
  35 class ProfilerMwprof extends Profiler {
  36
  37         // Message types
  38
  39         const TYPE_SINGLE = 1;
  40         const TYPE_RUNNING = 2;
  41
  42         /**
  43          * Indicate that this Profiler subclass is persistent.
  44          *
  45          * Called by Parser::braceSubstitution. If true, the parser will not
  46          * generate per-title profiling sections, to avoid overloading the
  47          * profiling data collector.
  48          *
  49          * @return bool true
  50          */
  51         public function isPersistent() {
  52                 return true;
  53         }
  54
  55         /**
  56          * Start a profiling section.
  57          *
  58          * Marks the beginning of the function or code-block that should be time
  59          * and logged under some specific name.
  60          *
  61          * @param string $inName Section to start
  62          */
  63         public function profileIn( $inName ) {
  64                 $this->mWorkStack[] = array( $inName, count( $this->mWorkStack ),
  65                         $this->getTime(), $this->getTime( 'cpu' ) );
  66         }
  67
  68         /**
  69          * Produce an empty function report.
  70          *
  71          * ProfileMwprof does not provide a function report.
  72          *
  73          * @return string Empty string.
  74          */
  75         public function getFunctionReport() {
  76                 return '';
  77         }
  78
  79         /**
  80          * Close a profiling section.
  81          *
  82          * Marks the end of the function or code-block that should be timed and
  83          * logged under some specific name.
  84          *
  85          * @param string $outName Section to close
  86          */
  87         public function profileOut( $outName ) {
  88                 list( $inName, $inCount, $inWall, $inCpu ) = array_pop( $this->mWorkStack );
  89
  90                 // Check for unbalanced profileIn / profileOut calls.
  91                 // Bad entries are logged but not sent.
  92                 if ( $inName !== $outName ) {
  93                         $this->debugGroup( 'ProfilerUnbalanced', json_encode( array( $inName, $outName ) ) );
  94                         return;
  95                 }
  96
  97                 $elapsedCpu = $this->getTime( 'cpu' ) - $inCpu;
  98                 $elapsedWall = $this->getTime() - $inWall;
  99                 $this->updateEntry( $outName, $elapsedCpu, $elapsedWall );
 100                 $this->updateTrxProfiling( $outName, $elapsedWall );
 101         }
 102
 103         /**
 104          * Update an entry with timing data.
 105          *
 106          * @param string $name Section name
 107          * @param float $elapsedCpu elapsed CPU time
 108          * @param float $elapsedWall elapsed wall-clock time
 109          */
 110         public function updateEntry( $name, $elapsedCpu, $elapsedWall ) {
 111                 // If this is the first measurement for this entry, store plain values.
 112                 // Many profiled functions will only be called once per request.
 113                 if ( !isset( $this->mCollated[$name] ) ) {
 114                         $this->mCollated[$name] = array(
 115                                 'cpu'   => $elapsedCpu,
 116                                 'wall'  => $elapsedWall,
 117                                 'count' => 1,
 118                         );
 119                         return;
 120                 }
 121
 122                 $entry = &$this->mCollated[$name];
 123
 124                 // If it's the second measurement, convert the plain values to
 125                 // RunningStat instances, so we can push the incoming values on top.
 126                 if ( $entry['count'] === 1 ) {
 127                         $cpu = new RunningStat();
 128                         $cpu->push( $entry['cpu'] );
 129                         $entry['cpu'] = $cpu;
 130
 131                         $wall = new RunningStat();
 132                         $wall->push( $entry['wall'] );
 133                         $entry['wall'] = $wall;
 134                 }
 135
 136                 $entry['count']++;
 137                 $entry['cpu']->push( $elapsedCpu );
 138                 $entry['wall']->push( $elapsedWall );
 139         }
 140
 141         /**
 142          * Serialize profiling data and send to a profiling data aggregator.
 143          *
 144          * Individual entries are represented as arrays and then encoded using
 145          * MessagePack, an efficient binary data-interchange format. Encoded
 146          * entries are accumulated into a buffer and sent in batch via UDP to the
 147          * profiling data aggregator.
 148          */
 149         public function logData() {
 150                 global $wgUDPProfilerHost, $wgUDPProfilerPort;
 151
 152                 $this->close();
 153
 154                 $sock = socket_create( AF_INET, SOCK_DGRAM, SOL_UDP );
 155                 socket_connect( $sock, $wgUDPProfilerHost, $wgUDPProfilerPort );
 156                 $bufferLength = 0;
 157                 $buffer = '';
 158                 foreach ( $this->mCollated as $name => $entry ) {
 159                         $count = $entry['count'];
 160                         $cpu = $entry['cpu'];
 161                         $wall = $entry['wall'];
 162
 163                         if ( $count === 1 ) {
 164                                 $data = array( self::TYPE_SINGLE, $name, $cpu, $wall );
 165                         } else {
 166                                 $data = array( self::TYPE_RUNNING, $name, $count,
 167                                         $cpu->m1, $cpu->m2, $cpu->min, $cpu->max,
 168                                         $wall->m1, $wall->m2, $wall->min, $wall->max );
 169                         }
 170
 171                         $encoded = MWMessagePack::pack( $data );
 172                         $length = strlen( $encoded );
 173
 174                         // If adding this entry would cause the size of the buffer to
 175                         // exceed the standard ethernet MTU size less the UDP header,
 176                         // send all pending data and reset the buffer. Otherwise, continue
 177                         // accumulating entries into the current buffer.
 178                         if ( $length + $bufferLength > 1450 ) {
 179                                 socket_send( $sock, $buffer, $bufferLength, 0 );
 180                                 $buffer = '';
 181                                 $bufferLength = 0;
 182                         }
 183                         $buffer .= $encoded;
 184                         $bufferLength += $length;
 185                 }
 186                 if ( $bufferLength !== 0 ) {
 187                         socket_send( $sock, $buffer, $bufferLength, 0 );
 188                 }
 189         }
 190 }