Recycling an application pool shuts down all worker processes that are currently running and starts new ones. In addition, any PHP processes that are currently running are also restarted.
By default, IIS recycles worker processes every several hours. However, you can manually recycle application pools to free up memory and help increase speed and performance.
默认状态下,iis回每几个小时自动回收,当然你也可以手动回收,以便释放内存增加速度
这是godaddy的官方说明