filesystem and `softdep'

[Harry Putnam <hgp@sbcglobal.net>]

NEW TO OBSD ALERT 
Running (3.2)

Following threads here a ways back, a big one about setting up disks
and slices etc.  Early March, Subject: fdisk = fsck!
I noticed in several posted `mount' readouts that
those posters have `softdeps' as a flag on many slices.

Checking the mount man page it appears softdep is a desireable flag
and may enhance speed of read write operations.  (I'm running an older
TOSHIBA laptop with 96mb RAM [low by current standards])

I wondered if adding this option is as simple as editing /etc/fstab
and they will be in force on next reboot?  Are there any downsides to
using softdeps.  Any slices that should avoid them?

Also, I wondered if the flag can be set without a reboot?  Maybe
umount and remount using the -o switch to mount.

I used something close to default slicing taken from install instruc-
tions but wondered if I might be getting in over my `NEW TO OBSD' head
by adding that flag to these slices:

/dev/wd0a on / type ffs (local)
/dev/wd0g on /home type ffs (local, nodev, nosuid)
/dev/wd0d on /tmp type ffs (local, nodev, nosuid)
/dev/wd0f on /usr type ffs (local, nodev)
/dev/wd0e on /var type ffs (local, nodev, nosuid)

Specifically, the mount man page mentions a kernel option
FFS_SOFTUPDATES... is that built in to stock 3.2 kernel?