Re: [PATCH 0/2] Kexec jump: The first step to kexec base hibernation

Rafael J. Wysocki
2007-07-14T09:17:34Z

On Saturday, 14 July 2007 10:33, david@lang.hm wrote:
> by the way, a data point on kernel sizes
>
> -rw-r--r-- 1 root root 864648 Jul 14 00:53 vmlinuz.2.6.22.1.hibernate
> -rw-r--r-- 1 root root 659496 Jul 14 01:17 vmlinuz.2.6.22.1.hibernate.stripped
> -rw-r--r-- 1 root root 3948168 Jul 14 01:10 vmlinuz.2.6.22.1.running
>
> the running one matches the config I'm running on my home server, the
> hibernate is a pretty stripped down version, and the stripped is close to
> a minimum (including turning off printk and BUG()). All three are with all
> drivers built-in, no module support.
>
> this is on a amd64 64 bit system
>
> configs are available if anyone cares, the point is how much smaller a
> kernel could be if it doesn't need all the stuff that you put in your main
> kernel. In my case this includes not enabling the 3-ware card that holds
> my 12-disk raid array, instead the hibernate image would be stored on one
> of the scsi drives attached to the adaptec 78xx card.
>
> I expect that on a normal desktop/laptop with more features (like sound)
> the savings could be even more significant

But the kernel needs some data to work too (a 'struct page' for each memory
page etc.).

Greetings,
Rafael

--
"Premature optimization is the root of all evil." - Donald Knuth