amd64/152179: disklabel's Auto Defaults creates too small / partition on amd64

[Markus Hoenicka]

>Number:         152179
>Category:       amd64
>Synopsis:       disklabel's Auto Defaults creates too small / partition on amd64
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-amd64
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          change-request
>Submitter-Id:   current-users
>Arrival-Date:   Fri Nov 12 22:40:08 UTC 2010
>Closed-Date:
>Last-Modified:
>Originator:     Markus Hoenicka
>Release:        8.1-RELEASE
>Organization:
>Environment:
FreeBSD wombat.mininet 8.1-RELEASE FreeBSD 8.1-RELEASE #0: Sat Nov 13 20:29:49 CET 2010     root at wombat.mininet:/usr/obj/usr/src/sys/WOMBAT  amd64
>Description:
The handbook suggests in chap. 2.6.5:

"Users are encouraged to use the automatic partition layout called Auto Defaults by the FreeBSD partition editor."

Doing that results in a / partition of 512MB, although the entire disk is 500GB. This is enough for installing the base system. However, building and installing a custom kernel (a smaller one than GENERIC, fwiw) already overfills the / partition, causing the kernel installation to exit with an error.

I'd recommend to increase the default size of / to 1GB if the total size of the disk permits this. On my box, the current kernel, the old kernel, a good copy of the current kernel, and whatever sysinstall else puts into / take up approx. 775MB.

>How-To-Repeat:
Boot from an amd64 netinstall CD. Begin a standard installation. Use fdisk to allocate the entire HDD to FreeBSD. Enter disklabel and use the Auto Defaults option to automatically size the partitions.
>Fix:
It is easy to work around by manually sizing the partitions. Still, it might be a better idea to teach disklabel to use more appropriate defaults.

>Release-Note:
>Audit-Trail:
>Unformatted: