On Fri, 1 Dec 95 12:00:49 PST 
 jgraham@defender.VAS.viewlogic.com (Trouble Free RecepPFFFFFFFFFFFFFFFF) wrote:

 > The interesting thing is that, sure enough, at least locally, the
 > filesystem succeeds, now that I only have "options SUN4C" in my config
 > file.  I'm testing to see whether NFS still blows it up.

>From sparc/include/param.h:

/*
 * Three possible cases:
 *      sun4 only               8192 bytes/page
 *      sun4c/sun4m only        4096 bytes/page
 *      sun4/sun4c/sun4m        either of the above
 *
 * In the later case NBPG, PGOFSET, and PGSHIFT are encoded in variables
 * initialized early in locore.s.  Since they are variables, rather than
 * simple constants, the kernel will not perform slighly worse.
 */

If you have only (SUN4C || SUN4M) or only SUN4, NBPG is a constant, hence 
it doesn't lose.

--------------------------------------------------------------------------
Jason R. Thorpe                                       thorpej@nas.nasa.gov
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