syscons options and memory use

Dan Nelson dnelson at
Thu Mar 31 00:19:23 PST 2005

In the last episode (Mar 31), Ronald Klop said:
> On Thu, 31 Mar 2005 01:04:10 -0600, Dan Nelson <dnelson at>  
> wrote:
> >In the last episode (Mar 31), Ronald Klop said:
> >>The syscons manual page says:
> >>"    The following options will remove some features from the syscons
> >>     driver and save kernel memory.
> >>     [...]
> >>            This option removes mouse support in the syscons driver.
> >>            The mouse daemon moused(8) will fail if this option is
> >>            defined. This option implies the SC_NO_CUTPASTE option
> >>            too.
> >>"
> >>
> >>How much memory does this save (or how can I discover that)? Is it worth
> >>it on a 96MB PentiumII laptop?
> >
> >I would guess that the memory savings is probably on the order of
> >kilobytes.  Useful if you're trying to prevent excessive swapping on an
> >8MB system.  Not worth disabling on your system.
> How can I see the size of my kernel?
> I know vmstat -m and netstat -m, but from that info I don't see if I  
> reduced the memory footprint after disabling an option or device.

For the kernel size itself, just "ls -l /boot/kernel/kernel" :)  A more
interesting number might be the output of "sysctl hw.usermem", which I
believe is the amount of memory available to user processes.

	Dan Nelson
	dnelson at

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