Keeping track of sessions can be an expensive operation, especially as you grow beyond one server.
跟踪会话是一种成本很高的操作，尤其是在涉及多个服务器的情况下。
2
"It's just a very boring operation, it's like watching grass grow," Gheit says.
盖特表示：“这是个非常乏味的操作，就像观察小草生长一样。”
3
Resizing is a costly operation and should be avoided as much as possible. The default values for the grow/shrink trigger and the growby/shrinkby values are given in the example above.