On Thu, 20 Nov 1997, After 5 PM please slip brain through slot in door. wrote:

> Paul Kranenburg sez:
> /*
>  * This is where the fun starts.. the sun4c MMU uses a two-level translation
>  * table scheme. The most significant 14 bits of a virtual address are used
>  * to index the MMU context table. Two bits out these  14 are effectively
>  * not used leaving a table of 2**12 (4096) entries to be initialized.
>  * A couple of these are reserved for kernel-mode addresses, and pmap module
>  * also tries hard to avoid loading entries which aren't used, but you still
>  * need to fill many of these.  This is what takes a relatively long time..
> 
> 4096?  Does this mean that the actual number of process slots cannot
> exceed this number, i.e., can only 4096 processes run on the machine
> at any given time?
> 
> ...or am I way off base here and completely misreading what you've writ?
> 

There is code to recycle contexts if there are more processes than
contexts.  Whether anyone runs enough processes to excersize that code is
a rather interesting question.

=========================================================================
Eduardo Horvath				eeh@btr.com
"Cliffs are for climbing.  That's why God invented grappling hooks."
					- Benton Frasier