测试 php 的 hash_map / 纯数组 查找元素速度和资源占用情况

test-hash-map.php

<?php
function create_uuid()
{
    $str  = md5(uniqid(mt_rand(), true));
    $uuid = substr($str, 0, 8) . '-';
    $uuid .= substr($str, 8, 4) . '-';
    $uuid .= substr($str, 12, 4) . '-';
    $uuid .= substr($str, 16, 4) . '-';
    $uuid .= substr($str, 20, 12);

    return $uuid;
}

function getNiceFileSize($bytes, $binaryPrefix = true)
{
    if ($binaryPrefix) {
        $unit = ['B', 'KiB', 'MiB', 'GiB', 'TiB', 'PiB'];
        if ($bytes == 0) {
            return '0 ' . $unit[0];
        }

        return @round($bytes / pow(1024, ($i = floor(log($bytes, 1024)))), 2) . ' ' . (isset($unit[$i]) ? $unit[$i] : 'B');
    } else {
        $unit = ['B', 'KB', 'MB', 'GB', 'TB', 'PB'];
        if ($bytes == 0) {
            return '0 ' . $unit[0];
        }

        return @round($bytes / pow(1000, ($i = floor(log($bytes, 1000)))), 2) . ' ' . (isset($unit[$i]) ? $unit[$i] : 'B');
    }
}

@$mode = $argv[1];
$validMode = ['array', 'hash_map', 'isset_hash_map'];
if (!in_array($mode, $validMode)) {
    echo 'Mode must :' . implode('|', $validMode) . PHP_EOL;
    exit(1);
}
$max         = 500 * 10000;//500万种子
$needleIndex = random_int(1, $max);//保证这个种子在数组内的位置是随机的
$needle      = create_uuid();//用来检查的种子
$array       = [];
echo 'Current：' . getNiceFileSize(memory_get_usage(true)) . PHP_EOL;
$start = microtime(true);
for ($i = 1; $i <= $max; $i++) {
    if ($i === $needleIndex) {
        $uuid = $needle;
    } else {
        $uuid = create_uuid();
    }
    if ($mode == 'array') {
        $array[] = $uuid;
    } else {
        $array[$uuid] = $uuid;
    }
}
$end = microtime(true);
echo 'Create Time: ' . sprintf('%0.15f', $end - $start) . PHP_EOL;

echo 'Total: ' . count($array) . PHP_EOL;
$searchTimes = 1000;//循环查找次数
$start       = microtime(true);
for ($i = 1; $i <= $searchTimes; $i++) {
    if ($mode == 'array') {
        in_array($needle, $array);
    } elseif ($mode == 'hash_map') {
        $array[$uuid];
    } else {
        isset($array[$needle]);
    }
}
$end = microtime(true);

echo 'Time for ' . $searchTimes . ' search: ' . sprintf('%0.15f', $end - $start) . PHP_EOL;
echo 'Peak：' . getNiceFileSize(memory_get_peak_usage(true)) . PHP_EOL;
echo 'Current：' . getNiceFileSize(memory_get_usage(true)) . PHP_EOL;

$ php scratch_1.php array
Current：2 MiB
Create Time: 5.587066173553467
Total: 5000000
Time for 1000 search: 31.601392030715942
Peak：564 MiB
Current：564 MiB
$ php scratch_1.php hash_map
Current：2 MiB
Create Time: 7.275614976882935
Total: 5000000
Time for 1000 search: 0.000067949295044
Peak：690 MiB
Current：596 MiB
$ php scratch_1.php isset_hash_map
Current：2 MiB
Create Time: 7.010115146636963
Total: 5000000
Time for 1000 search: 0.000063896179199
Peak：690 MiB
Current：596 MiB