hphp/tools/perf-call-graph.php

   1 #!/usr/local/bin/php -j
   2 <?hh
   3
   4 require(__DIR__.'/perf-lib.php');
   5
   6 # Returns true iff $sample contains a line containing $func.
   7 function contains_frame(Vector $sample, string $func): bool {
   8   foreach ($sample as $frame) {
   9     if (strstr($frame, $func) !== false) return true;
  10   }
  11   return false;
  12 }
  13
  14 # Node is used to construct to call graph. It contains an inclusive count of
  15 # samples for itself and all of its children, along with a map from function
  16 # names to children.
  17 class Node {
  18   private $kids = Map {};
  19
  20   public function __construct(private $name, private $count = 0) {}
  21
  22   # Add an edge from this function to $name, increasing the count of the child
  23   # Node by one and returning it.
  24   public function followEdge($name) {
  25     if (!isset($this->kids[$name])) $this->kids[$name] = new Node($name);
  26
  27     $new_node = $this->kids[$name];
  28     ++$new_node->count;
  29     return $new_node;
  30   }
  31
  32   # Print out the current node and all children.
  33   public function show(
  34     $total_count = null,
  35     $indent = '',
  36   ) {
  37     if ($total_count === null) {
  38       # We're the parent node and don't contain a useful name.
  39       $total_count = $this->count;
  40     } else {
  41       # Prune any subtrees that are <0.5% of the total to keep the output
  42       # readable.
  43       if ($this->count / $total_count < 0.005) return;
  44       printf("%s%.1f%% %s\n",
  45              $indent,
  46              $this->count / $total_count * 100,
  47              $this->name);
  48       $indent .= '- ';
  49     }
  50
  51     $items = $this->kids->items()->toVector();
  52     if ($items->count() == 0) return;
  53
  54     # If our only printable child is the body of this function, leave it out to
  55     # keep the results clean.
  56     if ($items[0][0] == '<body>' &&
  57         ($items->count() == 1 || $items[1][1]->count / $total_count < 0.005)) {
  58       return;
  59     }
  60
  61     usort(inout $items, ($a, $b) ==> $b[1]->count - $a[1]->count);
  62     foreach ($items as $pair) {
  63       $pair[1]->show($total_count, $indent);
  64     }
  65   }
  66 }
  67
  68 # Build and print a perf-annotated call graph of each stack trace in $samples.
  69 # If $top is set, each trace will be truncated at the highest frame containing
  70 # $top, if $root_last == false, or the lowest frame containing $top, if
  71 # $root_last == true.
  72 function treeify(
  73   Vector $samples,
  74   bool $reverse,
  75   bool $root_last,
  76   ?string $top
  77 ) {
  78   $root = new Node('', $samples->count());
  79   $step = $reverse ? 1 : -1;
  80   $search_step = $root_last ? -$step : $step;
  81
  82   foreach ($samples as $stack) {
  83     $first = $reverse ? 0 : $stack->count() - 1;
  84     $last = $reverse ? $stack->count() - 1 : 0;
  85     $search_first = $root_last ? $last : $first;
  86     $search_last = $root_last ? $first : $last;
  87
  88     if ($top !== null) {
  89       for ($i = $search_first; $i !== $search_last + $search_step;
  90            $i += $search_step) {
  91         if (strpos($stack[$i], $top) !== false) break;
  92       }
  93     } else {
  94       $i = $first;
  95     }
  96
  97     $node = $root;
  98     for (; $i !== $last + $step; $i += $step) {
  99       $func = $stack[$i];
 100       if ($func === 'HHVM::retInlHelper') continue;
 101       $func = preg_replace('/^PHP::.+\.php::/', 'PHP::', $func);
 102
 103       $node = $node->followEdge($func);
 104     }
 105     if (!$reverse) {
 106       # Add a final entry for exclusive time spent in the body of the bottom
 107       # function.
 108       $node->followEdge('<body>');
 109     }
 110   }
 111
 112   $root->show();
 113 }
 114
 115 function usage($script_name) {
 116   echo <<<EOT
 117 Usage:
 118
 119 $script_name [--reverse] [--root-last] [--exe <name>] [symbol]...
 120
 121 This script expects the output of "perf script --fields comm,ip,sym" on stdin.
 122 If no symbols are given, all samples will be combined into a single tree showing
 123 the call graph, annotated with the inclusive cost of each node.
 124
 125 If one symbol is given, the call graph will instead be built from samples with
 126 at least one frame containing the symbol. Samples will be truncated at the
 127 highest frame containing the symbol (or the lowest, if --root-last is given).
 128 Note that the symbol may appear anywhere in the function name, so using
 129 'Foo::translate' will match both 'Foo::translate' and 'Foo::translateFrob'.
 130 If you just want Foo::translate, use 'Foo::translate('.
 131
 132 Finally, if multiple symbols are given, a summary will be printed showing the
 133 total number of samples, and how many samples contain each symbol.
 134
 135 If --reverse is given, the call graph will be inverted before tree formation,
 136 showing callers of any given symbols, rather than callees.
 137
 138 By default, only samples from the 'hhvm' binary will be considered. Giving
 139 --exe with an argument overrides this.
 140 EOT;
 141 }
 142
 143 function main($argv) {
 144   ini_set('memory_limit', '64G');
 145   if (posix_isatty(STDIN)) {
 146     usage($argv[0]);
 147     return 1;
 148   }
 149   array_shift(&$argv);
 150
 151   $reverse = false;
 152   $root_last = false;
 153   $functions = Set {};
 154   $exe = 'hhvm';
 155   for ($i = 0; $i < count($argv); ++$i) {
 156     $arg = $argv[$i];
 157     if ($arg=== '--reverse') {
 158       $reverse = true;
 159     } else if ($arg === '--root-last') {
 160       $root_last = true;
 161     } else if ($arg === '--exe') {
 162       $exe = $argv[++$i];
 163     } else {
 164       $functions->add($arg);
 165     }
 166   }
 167
 168   $samples = read_perf_samples(STDIN, $exe);
 169   $subsamples = Map {'all' => $samples};
 170   foreach ($functions as $f) {
 171     $subsamples[$f] = $samples->filter($s ==> contains_frame($s, $f));
 172   }
 173
 174   if ($functions->isEmpty()) {
 175     treeify($subsamples['all'], $reverse, $root_last, null);
 176   } else if ($functions->count() === 1) {
 177     $func = $functions->firstValue();
 178     $sub = $subsamples[$func];
 179     printf("Looking for pattern *%s*. %d of %d total samples (%.2f%%)\n\n",
 180            $func, $sub->count(), $samples->count(),
 181            $sub->count() / $samples->count() * 100);
 182     treeify($sub, $reverse, $root_last, $func);
 183   } else {
 184     foreach ($subsamples as $k => $v) {
 185       printf(
 186         "%8d %5.1f %s\n", $v->count(), $v->count() / $samples->count() * 100, $k
 187       );
 188     }
 189   }
 190
 191   return 0;
 192 }
 193
 194 exit(main($argv));