Drupal 7 PHP内存耗尽问题求助：调大内存仍报错

初始4G内存限制下的报错日志 #

PHP Fatal error: Allowed memory size of 4294967296 bytes exhausted (tried to allocate 28672 bytes) in /home/....com/public_html/.../includes/cache.inc on line 361
PHP Fatal error: Allowed memory size of 4294967296 bytes exhausted (tried to allocate 262144 bytes) in /home/....com/public_html/.../includes/database/database.inc on line 731
PHP Fatal error: Allowed memory size of 4294967296 bytes exhausted (tried to allocate 16384 bytes) in /home/....com/public_html/.../includes/cache.inc on line 449
PHP Fatal error: Allowed memory size of 4294967296 bytes exhausted (tried to allocate 16384 bytes) in /home/....com/public_html/.../includes/cache.inc on line 449
PHP Fatal error: Allowed memory size of 4294967296 bytes exhausted (tried to allocate 16384 bytes) in /home/....com/public_html/.../includes/cache.inc on line 449
PHP Fatal error: Allowed memory size of 4294967296 bytes exhausted (tried to allocate 20480 bytes) in /home/....com/public_html/.../includes/cache.inc on line 449
PHP Fatal error: Allowed memory size of 4294967296 bytes exhausted (tried to allocate 16384 bytes) in /home/....com/public_html/.../includes/cache.inc on line 449
PHP Fatal error: Allowed memory size of 4294967296 bytes exhausted (tried to allocate 32768 bytes) in /home/....com/public_html/.../includes/database/database.inc on line 2284

报错相关代码片段 #

cache.inc 第361行所在函数 #

# function contains line 361
function getMultiple(&$cids) {
    try {
      // Garbage collection necessary when enforcing a minimum cache lifetime.
      $this->garbageCollection($this->bin);

      // When serving cached pages, the overhead of using db_select() was found
      // to add around 30% overhead to the request. Since $this->bin is a
      // variable, this means the call to db_query() here uses a concatenated
      // string. This is highly discouraged under any other circumstances, and
      // is used here only due to the performance overhead we would incur
      // otherwise. When serving an uncached page, the overhead of using
      // db_select() is a much smaller proportion of the request.
      $result = db_query('SELECT cid, data, created, expire, serialized FROM {' . db_escape_table($this->bin) . '} WHERE cid IN (:cids)', array(':cids' => $cids));
      $cache = array();
// #361     
 foreach ($result as $item) { 
        $item = $this->prepareItem($item);
        if ($item) {
          $cache[$item->cid] = $item;
        }
      }
      $cids = array_diff($cids, array_keys($cache));
      return $cache;
    }
    catch (Exception $e) {
      // If the database is never going to be available, cache requests should
      // return FALSE in order to allow exception handling to occur.
      return array();
    }
  }

cache.inc 第449行所在函数 #

#function contains line 449
protected function prepareItem($cache) {
    global $user;

    if (!isset($cache->data)) {
      return FALSE;
    }
    // If the cached data is temporary and subject to a per-user minimum
    // lifetime, compare the cache entry timestamp with the user session
    // cache_expiration timestamp. If the cache entry is too old, ignore it.
    if ($cache->expire != CACHE_PERMANENT && variable_get('cache_lifetime', 0) && isset($_SESSION['cache_expiration'][$this->bin]) && $_SESSION['cache_expiration'][$this->bin] > $cache->created) {
      // Ignore cache data that is too old and thus not valid for this user.
      return FALSE;
    }

    // If the data is permanent or not subject to a minimum cache lifetime,
    // unserialize and return the cached data.
//#449
    if ($cache->serialized) {
      $cache->data = unserialize($cache->data);
    }

    return $cache;
  }

当前环境配置 #

PHP version:    7.4.33
PHP memory_limit:   4G
PHP post_max_size:  16M
PHP upload_max_filesize:    4M
PHP max_input_vars: 1000
PHP max_execution_time: 60
OS: Almalinux 9
webserver: Apache
Drupal version: V 7.101

调整内存限制到7G后的报错日志 #

PHP Fatal error: Allowed memory size of 7516192768 bytes exhausted (tried to allocate 32768 bytes) in /home/.....com/public_html/..../includes/cache.inc on line 361
PHP Fatal error: Allowed memory size of 7516192768 bytes exhausted (tried to allocate 20480 bytes) in /home/.....com/public_html/..../includes/cache.inc on line 449
PHP Fatal error: Allowed memory size of 7516192768 bytes exhausted (tried to allocate 20480 bytes) in /home/.....com/public_html/..../includes/cache.inc on line 449
PHP Fatal error: Allowed memory size of 7516192768 bytes exhausted (tried to allocate 20480 bytes) in /home/.....com/public_html/..../includes/cache.inc on line 449
PHP Fatal error: Allowed memory size of 7516192768 bytes exhausted (tried to allocate 20480 bytes) in /home/.....com/public_html/..../includes/cache.inc on line 449
PHP Fatal error: Allowed memory size of 7516192768 bytes exhausted (tried to allocate 262144 bytes) in /home/.....com/public_html/..../includes/database/database.inc on line 731

求助说明 #

不清楚错误根源，调整memory_limit到7G仍无法解决问题，曾设置memory_limit = -1导致服务器24小时后崩溃，求排查方向。

内容的提问来源于stack exchange，提问作者hoangvnn