> You want WRKOBJDIR=/var/temp and OBJHOSTNAME=yes, so every machine
> gets a working directory of its own. See line 522ff in bsd.prefs.mk.

You could use:

  WRKOBJDIR?=/var/temp/${MACHINE_ARCH}

in /etc/mk.conf.  This will allow it to be overidden on the command line
(the ?=) and allow all machines of the same architecture to share builds.

You might also find that a periodic:

  rm -rf /var/tmp/<TARGET_ARCH>/*

on the NFS server is faster than running:

  make clean

on the slower machines.

J

-- 
  My other computer also runs NetBSD    /        Sailing at Newbiggin
        http://www.netbsd.org/        /   http://www.newbigginsailingclub.org/