pm-suspend 和 pm-suspend-hybrid 有什么区别？

Question

我阅读了他们两个的手册页，但我无法弄清楚其中的区别。

手册页说：

Hybrid-suspend is the process where the
           system does everything it needs to hibernate,
           but suspends instead of shutting down. This
           means that your computer can wake up quicker
           than for normal hibernation if you do not run
           out of power

这不是和 suspend 一样吗？

Answer 1

pm-suspend 基本上关闭 CPU，但保持内存通电。这可以快速恢复，但如果电量耗尽，内存中的数据就会丢失。混合挂起会将内存内容保存到磁盘然后挂起，您可以像正常挂起一样从中唤醒，但是如果您断电，您可以通电，机器将从磁盘加载保存的状态并恢复，很像传统的休眠简历。

Answer 2

手册页 pm-action

    pm-suspend
       During suspend most devices are shutdown, and system state is saved
       in RAM. The system still requires power in this state. Most modern
       systems require 3 to 5 seconds to enter and leave suspend, and most
       laptops can stay in suspend mode for 1 to 3 days before exhausting
       their battery.

   pm-hibernate
       During hibernate the system is fully powered off, and system state
       is saved to disk. The system does not require power, and can stay
       in hibernate mode indefinitely. Most modern systems require 15 to
       45 seconds to enter and leave hibernate, and entering and leaving
       hibernate takes longer when you have more memory.

   pm-suspend-hybrid
       Hybrid-suspend is the process where the system does everything it
       needs to hibernate, but suspends instead of shutting down. This
       means that your computer can wake up quicker than for normal
       hibernation if you do not run out of power, and you can resume even
       if you run out of power. s2both(8) is an hybrid-suspend
       implementation.

我想这里的区别在于系统状态保存到磁盘（而不是 RAM），但系统没有完全关闭（如休眠）而是挂起。