(mongodb >=1.0.0)
MongoDB\Driver\Server::getLatency — Returns the latency of this server in milliseconds
   Returns the latency of this server in milliseconds. This is the client's
   measured
   » round trip time
   of a hello command.
  
此函数没有参数。
   Returns the latency of this server in milliseconds, or null if no latency
   has been measured (e.g. client is connected to a load balancer).
  
| 版本 | 说明 | 
|---|---|
| PECL mongodb 1.11.0 | This method will return nullif no latency has been measured. In
        earlier versions, an integer was always returned and an unset value
        might be reported as-1. | 
示例 #1 MongoDB\Driver\Server::getLatency() example
<?php
$manager = new MongoDB\Driver\Manager("mongodb://localhost:27017/");
$rp = new MongoDB\Driver\ReadPreference(MongoDB\Driver\ReadPreference::RP_PRIMARY);
$server = $manager->selectServer($rp);
var_dump($server->getLatency());
?>
以上例程的输出类似于:
int(592)