Swoole 4.5.6支持零拷贝JSON或PHP反序列化

$packet = $header + $body + $footer

// 先进行 substr，这时会产生内存拷贝，从 $packet 复制数据到 $body_str
$body_str = substr($packet, 4, strlen($packet) - 4 - 2);
// 反序列化之后 $body_str 这块内存不再使用，会在函数退出时释放
$body = json_decode($body_str, true);

$body = swoole_substr_json_decode($packet, $header_length);
$body = swoole_substr_unserialize($packet, $header_length);

<?php
error_reporting(E_ALL);
$a['hello'] = base64_encode(random_bytes(1000));
$a['world'] = 'hello';
$a['int'] = rand(1, 999999);
$a['list'] = ['a,', 'b', 'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx'];
$val = serialize($a);
$str = pack('N', strlen($val)).$val."\r\n";
$n = 100000;
$s = microtime(true);
while($n--) {
    $l = strlen($str) - 6;
    // var_dump(unserialize(substr($str, 4, $l)));
    var_dump(swoole_substr_unserialize($str, 4, $l));
}
echo "cost: ".(microtime(true)-$s)."n";

htf@htf-ThinkPad-T470p:~/workspace/debug$ php s.php
cost: 2.2559139728546
htf@htf-ThinkPad-T470p:~/workspace/debug$ php s.php
cost: 1.9821600914001