php函数算法优化技巧：分布式系统中的性能考量

class Person {
  public $name;
}

$person = new Person();
echo $person->getName(); // 无谓的函数调用，直接访问属性更有效率
echo $person->name; // 直接访问属性

use Parallel\{Parallel, Task};

$numbers = range(1, 1000000);

// 串行处理
$primeNumbers = Parallel\map($numbers, function ($n) {
  if ($n <= 1) return false;
  $sqrt = (int)sqrt($n);
  for ($i = 2; $i <= $sqrt; $i++) {
    if ($n % $i == 0) return false;
  }
  return true;
});

// 并行处理
$parallelPrimeNumbers = Parallel::map($numbers, function ($n) {
  return is_prime($n);
});

function calculateTotalCost($cart) {
  $totalCost = 0;
  foreach ($cart as $item) {
    $totalCost += $item['quantity'] * $item['price'];
  }
  return $totalCost;
}

function optimizedCalculateTotalCost($cart) {
  $totalCost = 0;
  foreach ($cart as $item) {
    $totalCost += $item['quantity'] * $item['price'];
  }
  return $totalCost;
}

// 缓存示例
$cache = new Cache();
$cachedTotalCost = $cache->get('total_cost');
if ($cachedTotalCost !== false) {
  return $cachedTotalCost;
}
$totalCost = optimizedCalculateTotalCost($cart);
$cache->set('total_cost', $totalCost);
return $totalCost;

// 集合类示例
$cart = new SplFixedArray(count($arrayCart));
foreach ($arrayCart as $i => $item) {
  $cart[$i] = ['quantity' => $item['quantity'], 'price' => $item['price']];
}