Re: Small kernel for sun3

[email protected] (Christos Zoulas) Sun, 25 Jan 2009 00:53:21 +0000 (UTC)
Newsgroups gmane.os.netbsd.ports.sun3
Message-ID <[email protected]>
In article <alpine.NEB.2.00.0901250022130.20410@localhost>,
David Brownlee  <[email protected]> wrote:
> 	I've been playing around with Izumi's kernel config, looking
> 	where to save space, and came up with an interesting issue
> 	- specifically how to determine kernel size.
>
> 	For example the two kernels below are very similar in size
> 	as reported by ls (the second is 673 bytes larger), but
> 	when using 'size' the second is 130620 bytes (just under
> 	128K) smaller.
>
>ls -l: 1360 -rwxr-xr-x  1 abs  wheel  1371776 Jan 25 00:07 netbsd
>  size: 1055608   26916  207584 1290108  13af7c netbsd
>
>ls -l: 1360 -rwxr-xr-x  1 abs  wheel  1372449 Jan 25 00:20 netbsd
>  size: 1056060   26916   76512 1159488  11b140 netbsd
>
> 	The difference is due to using a slighly patched r1.11
> 	version of netinet/ip_id.c, which does not include a 128K
> 	table for returning a random IP 'id' number.
>http://cvsweb.netbsd.org/bsdweb.cgi/src/sys/netinet/ip_id.c?only_with_tag=MAIN
>
> 	The first may look slightly smaller, but the second will use
> 	128K less memory when loaded.
>
> 	Its almost worth keeping the old netinet/ip_id.c around for
> 	conditional compiling for install and very low memory kernels...
>

Well, you could allocate the array dynamically but using the old ip_id
code we'll lead to predictable sequence numbers again.

christos