Subject: swap device, pageout on pmax broken?
To: Per Fogelstrom <pefo@enea.se>
From: Jonathan Stone <jonathan@DSG.Stanford.EDU>
List: tech-kern
Date: 08/02/1995 03:37:20
pefo@enea.se (Per Fogelstrom) writes:
>And will not work before the line 
>        dev_t swapdev = makedev(1, 0);
>in conf.c is fixed so it points at the swap pseudo device instead
>of a dummy (nodev).

Pageout seems to be thoroughly broken on pmaxes.  The cdevsw says:

struct cdevsw	cdevsw[] =
{
	cdev_cn_init(1,cn),		/* 0: virtual console */
	cdev_swap_init(1,sw),		/* 1: /dev/drum (swap pseudo-device) */

   /* ... */
}

so makedev(1, 0) isn't _entirely_ wrong.

Is swapdev meant to be the *block* device or the *raw* device?
Do they have to be the same major number for the swap device?
Or is it maybe chrtoblktb[] that's broken?  Or something else?
I tried changing the "(1, 0)" to (4, 0)" and ran enough copies
of a 16Mbyte page-dirtier to exhaust memory, but I didn't
notice any difference between the two majors for swapdev.


I probably broke the swap device numbers about a year ago, trying to
be consistent with  Ultrix device numbers.  That was a great help for
initial bootstrapping (which involved booting NetBSD off Ultrix
partitions), but is no longer necessary.


The block swap device on NetBSD/pmax is major 4, and the char
device is major 1.  If someone could tell me definitely that
that's broken, I'll fix it; but right now I'm trying to get new-style
config working.

thanks,
-Jonathan