Sleep mode

Sleep mode is a low power mode for electronic devices such as computers, televisions, and remote controlled devices. These modes save significantly on electrical consumption compared to leaving a device fully on and, upon resume, allow the user to avoid having to reissue instructions or to wait for a machine to reboot. Many devices signify this power mode with a pulsed or red colored LED power light.

Computers

In computers, entering a sleep state is roughly equivalent to "pausing" the state of the machine. When restored, the operation continues from the same point, having the same applications and files open.

Sleep

Sleep mode has gone by various names, including Stand By (for Microsoft Windows 98-Server 2003), Sleep (for Mac OS 8-Mac OS X, Windows Vista, Windows 7, Windows 8, Windows 10, Windows Server 2008), Suspend (Windows 95) and Suspend to RAM (Linux). Machine state is held in RAM and, when placed in sleep mode, the computer cuts power to unneeded subsystems and places the RAM into a minimum power state, just sufficient to retain its data. Because of the large power saving, most laptops automatically enter this mode when the computer is running on batteries and the lid is closed. If undesired, the behavior can be altered in the operating system settings.

TuxOnIce

TuxOnIce (formerly known as Suspend2) is an implementation of the suspend-to-disk (or hibernate) feature which is available as patches for the 2.6 Linux kernel. During the 2.5 kernel era, Pavel Machek forked the original out-of-tree version of swsusp (then at approximately beta 10) and got it merged into the vanilla kernel, while development continued in the swsusp/Suspend2/TuxOnIce line. TuxOnIce includes support for SMP, highmem and preemption. Its major advantages over swsusp are: