On Tue, May 19, 2009 at 4:47 PM, Martin Bochnig <martin at martux.org> wrote:
> Hello OS/Net,
>
> may this be a bug related to my specific hardware {#0}, or is it a new
> feature to dramatically speed up reboots?
> On SXCE build 114 x86 I noticed, that when I run
>
> # init 6
>
> the system properly shuts down, syncs filesystems and then _instantly_
> (after less than a second) reinitializes the kernel!
> Without going to POST/BIOS and - especially nice - without having Grub
> to download the ramdisk image.
>
> This saves about 2 to 3 minutes time per reboot on my machine (Plus:
> It avoids problems if you run a system without ALOM/RSC as server if
> you are not around, the system needs to be rebooted [simply via ssh to
> the running host] or if it ever panics, yet it cannot be ensured that
> somebody is around, when the boot disk is not set as the default boot
> device in the BIOS, where manual interaction during POST is needed to
> pick the right device via F^12 through the BIOS's boot menu. In case
> of the described soft-reboot all that is no problem at all, because
> the right OS instance just gets rebooted, nothing to worry about!).
> It feels, as if you reboot a zone. Only that it is the global zone.
>
> tmpfs gets re-initialized from scratch.
> Files in /tmp do not surivive such a soft-reboot, just as it has
> always been with a normal hard-reboot.
>
> At first I thought of a potential ACPI problem to be the cause. Yet
> init 5 (or poweroff) does poweroff and switch off this Laptop.
> So even if this is a hardware related bug (is it?), please implement
> it that way.
> It works great.
>
>
> I didn't yet google for it.
> Could somebody of you please provide me (a pointer to) more
> information about it?
>
> {#0}
> FUJITSU SIEMENS AMILO Notebook Pa 3515
> BIOS Configuration: Phoenix Technologies LTD V1.16 ? ? ? ? ? ?01/06/2009I believe fast reboot was enabled as the default in recent builds (this can be toggled). In addition there was some work done to speed up the shutdown process as well.
