[BusyBox] Re: busybox digest, Vol 1 #258 - 3 msgs

[Mark Whitley]

On Wed, Jan 24, 2001 at 08:43:30AM +1300, Alex King wrote:
> 
> I was just wondering, is the bss actually pulled into memory?  Appart
> from page table overhead, this should only use memory if the applications
> actually touch the bss, ie it should be pulled in in 4k pages as
> needed?

This was addressed before, but here's the scoop:

Taken from FOLDOC: (http://www.foldoc.org)

	Block Started by Symbol

	(BSS) The uninitialised data segment produced by Unix linkers. The other
	segments are the "text" segment which contains the program code and the
	"data" segment contains initialised data. Objects in the bss segment have
	only a name and a size but no value.

Hence, the BSS does not exist on the disk, per se, except as a name and a
size. The value reported from the 'size' command to show the size of the BSS
is the run-time size, not the disk size. The gain from eliminating big static
buffers is that much less memory is used at run-time, at the cost of a
slightly larger size on disk. I consider this to be an overall win.


Mark Whitley
markw at lineo.com