Compare Modified GC

README.md

To set this up, have 2 builds of PHP, one using the "master" branch, and one using my refactor branch. Configure the paths to the SAPI at the top of benchmark.php.

Note that it's hard-coded to look for php-src/Zend/bench.php, php-src/Zend/micro_bench.php and gc_test.php.

benchmark.php

<?php
function err($msg) { file_put_contents('php://stderr', $msg); }
$sapis = array(
        'core' => 'php-src2/sapi/cli/php',
        'modified' => 'php-src/sapi/cli/php',
);
$results = array();
foreach ($sapis as $name => $sapi) {
        err("\nRunning $name\n");
        $bm = new Benchmarker($sapi);
        $result = $bm->benchmark();
        $results[$name] = array();
        foreach ($result as $test => $values) {
                $results[$name][$test] = array(
                        'min' => min($values),
                        'max' => max($values),
                        'average' => array_sum($values) / count($values),
                );
        }
}

foreach ($results['core'] as $test => $result) {
        $modres = $results['modified'][$test];
        echo "\n$test\n";
        echo " Core:     {$result['min']} - {$result['average']} - {$result['max']}\n";
        echo " Modified: {$modres['min']} - {$modres['average']} - {$modres['max']}\n";
        echo " Diff: " . number_format((($result['min'] - $modres['min']) / $result['min']) * 100, 5) . '% - ';
        echo number_format((($result['average'] - $modres['average']) / $result['max']) * 100, 5) . '% - ';
        echo number_format((($result['max'] - $modres['max']) / $result['max']) * 100, 5) . "\n";
}


class Benchmarker {
        protected $sapi;
        protected $runs = 10;

        public function __construct($sapi) {
                $this->sapi = $sapi;
        }

        public function benchmark() {
                $results = array_merge(
                        $this->benchmarkFull(),
                        $this->benchmarkMicro(),
                        $this->benchmarkGC()
                );
                return $results;
        }

        public function benchmarkFull() {
                $cmd = $this->sapi . ' php-src/Zend/bench.php';
                $results = array();
                for ($i = 0; $i < $this->runs; $i++) {
                        err('.');
                        $result = shell_exec($cmd);
                        $tests = explode("\n", $result);
                        foreach ($tests as $test) {
                                if (empty($test) || $test[0] === '-' || '' == trim($test)) continue;
                                list ($name, $value) = preg_split("(\s+)", trim($test));
                                $name = 'Full: ' . $name;
                                if (!isset($results[$name])) {
                                        $results[$name] = array();
                                }
                                $results[$name][] = (float) $value;
                        }
                }
                return $results;
        }

        public function benchmarkGC() {
                $cmd = $this->sapi . ' -d memory_limit=512M php-src/test.php';
                $results = array('GC' => array());
                for ($i = 0; $i < $this->runs; $i++) {
                        err('-');
                        $m = microtime(true);
                        shell_exec($cmd);
                        $e = microtime(true);
                        $results['GC'][] = $e - $m;
                }
                return $results;
        }

        public function benchmarkMicro() {
                $cmd = $this->sapi . ' php-src/Zend/micro_bench.php';
                $results = array();
                for ($i = 0; $i < $this->runs; $i++) {
                        err('_');
                        $result = shell_exec($cmd);
                        $tests = explode("\n", $result);
                        foreach ($tests as $test) {
                                if (empty($test) || $test[0] === '-' || '' == trim($test)) continue;
                                list ($name, $value) = preg_split("(\s+(?=\d+\.))", trim($test));
                                if (!$name || !$value) {
                                        var_dump($test, $result);
                                        die();
                                }
                                $name = 'Micro: ' . $name;
                                if (!isset($results[$name])) {
                                        $results[$name] = array();
                                }
                                $results[$name][] = (float) $value;
                        }
                }
                return $results;
        }

}

gc_test.php

<?php
$counter = 0;
$a = array(&$a);
function fill (&$a, $i = 3, &$counter) {
    if ($counter++ > 200000) die();
    if (!$i--) return;
    foreach ($a as &$tmp) {
        $tmp = array($tmp, &$a);
        fill($tmp, $i, $counter);
    }
}
fill($a, 3, $counter);

results.txt

Each test ran a total of 10 times.

Diff percentages are "Modified" is faster. So a positive percentage is a faster result in the modified algorithm, a negative percentage is a slower result in the modified algorithm.

Full: simple
 Core:     0.104 - 0.1053 - 0.109
 Modified: 0.103 - 0.105 - 0.107
 Diff: 0.96154% - 0.27523% - 1.83486

Full: simplecall
 Core:     0.099 - 0.103 - 0.115
 Modified: 0.101 - 0.1046 - 0.114
 Diff: -2.02020% - -1.39130% - 0.86957

Full: simpleucall
 Core:     0.098 - 0.1032 - 0.123
 Modified: 0.097 - 0.1004 - 0.109
 Diff: 1.02041% - 2.27642% - 11.38211

Full: simpleudcall
 Core:     0.1 - 0.1032 - 0.107
 Modified: 0.1 - 0.1032 - 0.111
 Diff: 0.00000% - 0.00000% - -3.73832

Full: mandel
 Core:     0.272 - 0.293 - 0.366
 Modified: 0.256 - 0.263 - 0.283
 Diff: 5.88235% - 8.19672% - 22.67760

Full: mandel2
 Core:     0.284 - 0.2924 - 0.298
 Modified: 0.279 - 0.2901 - 0.31
 Diff: 1.76056% - 0.77181% - -4.02685

Full: ackermann(7)
 Core:     0.114 - 0.1181 - 0.123
 Modified: 0.114 - 0.1164 - 0.121
 Diff: 0.00000% - 1.38211% - 1.62602

Full: ary(50000)
 Core:     0.019 - 0.0204 - 0.023
 Modified: 0.019 - 0.02 - 0.021
 Diff: 0.00000% - 1.73913% - 8.69565

Full: ary2(50000)
 Core:     0.018 - 0.0187 - 0.019
 Modified: 0.019 - 0.0191 - 0.02
 Diff: -5.55556% - -2.10526% - -5.26316

Full: ary3(2000)
 Core:     0.144 - 0.1491 - 0.156
 Modified: 0.145 - 0.1504 - 0.156
 Diff: -0.69444% - -0.83333% - 0.00000

Full: fibo(30)
 Core:     0.303 - 0.3114 - 0.323
 Modified: 0.325 - 0.3327 - 0.341
 Diff: -7.26073% - -6.59443% - -5.57276

Full: hash1(50000)
 Core:     0.032 - 0.0331 - 0.035
 Modified: 0.032 - 0.0329 - 0.034
 Diff: 0.00000% - 0.57143% - 2.85714

Full: hash2(500)
 Core:     0.035 - 0.0362 - 0.041
 Modified: 0.034 - 0.036 - 0.039
 Diff: 2.85714% - 0.48780% - 4.87805

Full: heapsort(20000)
 Core:     0.081 - 0.0851 - 0.088
 Modified: 0.079 - 0.0837 - 0.098
 Diff: 2.46914% - 1.59091% - -11.36364

Full: matrix(20)
 Core:     0.087 - 0.09 - 0.096
 Modified: 0.086 - 0.0902 - 0.095
 Diff: 1.14943% - -0.20833% - 1.04167

Full: nestedloop(12)
 Core:     0.17 - 0.1767 - 0.196
 Modified: 0.171 - 0.1763 - 0.2
 Diff: -0.58824% - 0.20408% - -2.04082

Full: sieve(30)
 Core:     0.089 - 0.0932 - 0.112
 Modified: 0.095 - 0.0971 - 0.103
 Diff: -6.74157% - -3.48214% - 8.03571

Full: strcat(200000)
 Core:     0.011 - 0.0116 - 0.014
 Modified: 0.008 - 0.0108 - 0.013
 Diff: 27.27273% - 5.71429% - 7.14286

Micro: empty_loop
 Core:     0.106 - 0.1081 - 0.113
 Modified: 0.104 - 0.1149 - 0.171
 Diff: 1.88679% - -6.01770% - -51.32743

Micro: func()
 Core:     0.303 - 0.3092 - 0.322
 Modified: 0.296 - 0.3038 - 0.316
 Diff: 2.31023% - 1.67702% - 1.86335

Micro: undef_func()
 Core:     0.307 - 0.3156 - 0.324
 Modified: 0.302 - 0.3111 - 0.328
 Diff: 1.62866% - 1.38889% - -1.23457

Micro: int_func()
 Core:     0.329 - 0.3361 - 0.357
 Modified: 0.258 - 0.2656 - 0.274
 Diff: 21.58055% - 19.74790% - 23.24930

Micro: $x = self::$x
 Core:     0.228 - 0.2363 - 0.269
 Modified: 0.221 - 0.2349 - 0.296
 Diff: 3.07018% - 0.52045% - -10.03717

Micro: self::$x = 0
 Core:     0.22 - 0.2265 - 0.231
 Modified: 0.317 - 0.3276 - 0.383
 Diff: -44.09091% - -43.76623% - -65.80087

Micro: isset(self::$x)
 Core:     0.205 - 0.2126 - 0.234
 Modified: 0.199 - 0.2105 - 0.264
 Diff: 2.92683% - 0.89744% - -12.82051

Micro: empty(self::$x)
 Core:     0.221 - 0.23 - 0.257
 Modified: 0.211 - 0.2301 - 0.275
 Diff: 4.52489% - -0.03891% - -7.00389

Micro: $x = Foo::$x
 Core:     0.201 - 0.2191 - 0.337
 Modified: 0.194 - 0.2022 - 0.213
 Diff: 3.48259% - 5.01484% - 36.79525

Micro: Foo::$x = 0
 Core:     0.193 - 0.1977 - 0.207
 Modified: 0.279 - 0.2888 - 0.301
 Diff: -44.55959% - -44.00966% - -45.41063

Micro: isset(Foo::$x)
 Core:     0.178 - 0.1851 - 0.2
 Modified: 0.175 - 0.1947 - 0.264
 Diff: 1.68539% - -4.80000% - -32.00000

Micro: empty(Foo::$x)
 Core:     0.191 - 0.2052 - 0.224
 Modified: 0.186 - 0.2024 - 0.222
 Diff: 2.61780% - 1.25000% - 0.89286

Micro: self::f()
 Core:     0.329 - 0.338 - 0.356
 Modified: 0.32 - 0.3307 - 0.344
 Diff: 2.73556% - 2.05056% - 3.37079

Micro: Foo::f()
 Core:     0.293 - 0.3011 - 0.314
 Modified: 0.288 - 0.2994 - 0.309
 Diff: 1.70648% - 0.54140% - 1.59236

Micro: $x = $this->x
 Core:     0.204 - 0.2116 - 0.218
 Modified: 0.202 - 0.2089 - 0.217
 Diff: 0.98039% - 1.23853% - 0.45872

Micro: $this->x = 0
 Core:     0.279 - 0.2883 - 0.321
 Modified: 0.268 - 0.2765 - 0.289
 Diff: 3.94265% - 3.67601% - 9.96885

Micro: $this->x += 2
 Core:     0.215 - 0.2225 - 0.243
 Modified: 0.208 - 0.2153 - 0.224
 Diff: 3.25581% - 2.96296% - 7.81893

Micro: ++$this->x
 Core:     0.187 - 0.1938 - 0.203
 Modified: 0.184 - 0.1893 - 0.201
 Diff: 1.60428% - 2.21675% - 0.98522

Micro: $this->x++
 Core:     0.264 - 0.2859 - 0.304
 Modified: 0.209 - 0.2195 - 0.258
 Diff: 20.83333% - 21.84211% - 15.13158

Micro: $this->x--
 Core:     0.207 - 0.2216 - 0.292
 Modified: 0.204 - 0.2126 - 0.224
 Diff: 1.44928% - 3.08219% - 23.28767

Micro: isset($this->x)
 Core:     0.196 - 0.2011 - 0.21
 Modified: 0.19 - 0.1977 - 0.214
 Diff: 3.06122% - 1.61905% - -1.90476

Micro: empty($this->x)
 Core:     0.206 - 0.2143 - 0.238
 Modified: 0.203 - 0.2101 - 0.224
 Diff: 1.45631% - 1.76471% - 5.88235

Micro: $this->f()
 Core:     0.336 - 0.3479 - 0.379
 Modified: 0.327 - 0.3354 - 0.352
 Diff: 2.67857% - 3.29815% - 7.12401

Micro: $x = Foo::TEST
 Core:     0.258 - 0.2686 - 0.292
 Modified: 0.191 - 0.1952 - 0.201
 Diff: 25.96899% - 25.13699% - 31.16438

Micro: new Foo()
 Core:     0.828 - 0.8442 - 0.886
 Modified: 0.685 - 0.7015 - 0.729
 Diff: 17.27053% - 16.10609% - 17.72009

Micro: $x = TEST
 Core:     0.152 - 0.1571 - 0.176
 Modified: 0.15 - 0.155 - 0.165
 Diff: 1.31579% - 1.19318% - 6.25000

Micro: $x = $_GET
 Core:     0.318 - 0.3218 - 0.327
 Modified: 0.216 - 0.2212 - 0.231
 Diff: 32.07547% - 30.76453% - 29.35780

Micro: $x = $GLOBALS['v']
 Core:     0.283 - 0.2885 - 0.301
 Modified: 0.28 - 0.293 - 0.371
 Diff: 1.06007% - -1.49502% - -23.25581

Micro: $x = $hash['v']
 Core:     0.209 - 0.2173 - 0.225
 Modified: 0.207 - 0.2166 - 0.278
 Diff: 0.95694% - 0.31111% - -23.55556

Micro: $x = $str[0]
 Core:     0.303 - 0.3183 - 0.333
 Modified: 0.299 - 0.3101 - 0.333
 Diff: 1.32013% - 2.46246% - 0.00000

Micro: $x = $a ?: null
 Core:     0.297 - 0.3037 - 0.319
 Modified: 0.202 - 0.2077 - 0.212
 Diff: 31.98653% - 30.09404% - 33.54232

Micro: $x = $f ?: tmp
 Core:     0.271 - 0.2773 - 0.295
 Modified: 0.264 - 0.267 - 0.27
 Diff: 2.58303% - 3.49153% - 8.47458

Micro: $x = $f ? $f : $a
 Core:     0.347 - 0.3533 - 0.359
 Modified: 0.211 - 0.2153 - 0.22
 Diff: 39.19308% - 38.44011% - 38.71866

Micro: $x = $f ? $f : tmp
 Core:     0.353 - 0.3574 - 0.362
 Modified: 0.259 - 0.2703 - 0.29
 Diff: 26.62890% - 24.06077% - 19.88950





Full: Total
 Core:     2.094 - 2.1429 - 2.278
 Modified: 2.089 - 2.1323 - 2.208
 Diff: 0.23878% - 0.46532% - 3.07287

Micro: Total
 Core:     9.309 - 9.4995 - 9.878
 Modified: 8.62 - 8.8179 - 9.234
 Diff: 7.40144% - 6.90018% - 6.51954

GC
 Core:     0.5937340259552 - 0.60687265396118 - 0.62824201583862
 Modified: 0.43920111656189 - 0.44599950313568 - 0.47265577316284
 Diff: 26.02730% - 25.60688% - 24.76534