syscons options and memory use

Peter Jeremy PeterJeremy at
Thu Mar 31 01:17:55 PST 2005

On Thu, 2005-Mar-31 09:53:59 +0200, Ronald Klop 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?

It basically removes scmouse.c, sysmouse.c and a largish chunk of code in
scvgarndr.c - my estimate is about 9KB.  You can probably do better looking
elsewhere.  For loadable devices, looking at the module size is a good

>How can I see the size of my kernel?

server% size /boot/kernel/kernel 
   text    data     bss     dec     hex filename
3045945  229911  978784 4254640  40ebb0 /boot/kernel/kernel

Remember that this doesn't include dynamic memory allocated by the
kernel which can be quite significant.  Look at the "real memory"
and "avail memory" lines in your boot dmesg to get a better idea
of the basic kernel memory requirements.

Peter Jeremy

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