NetBSD/sys/arch/sun3/include/vmparam.h

#define USRTEXT         NBPG
#define USRSTACK        (0-NBPG)

/*
 * Virtual memory related constants, all in bytes
 */
#ifndef MAXTSIZ
#define	MAXTSIZ		(6*1024*1024)		/* max text size */
#endif
#ifndef DFLDSIZ
#define	DFLDSIZ		(8*1024*1024)		/* initial data size limit */
#endif
#ifndef MAXDSIZ
#define	MAXDSIZ		(16*1024*1024)		/* max data size */
#endif
#ifndef	DFLSSIZ
#define	DFLSSIZ		(512*1024)		/* initial stack size limit */
#endif
#ifndef	MAXSSIZ
#define	MAXSSIZ		MAXDSIZ			/* max stack size */
#endif

/*
 * Default sizes of swap allocation chunks (see dmap.h).
 * The actual values may be changed in vminit() based on MAXDSIZ.
 * With MAXDSIZ of 16Mb and NDMAP of 38, dmmax will be 1024.
 * DMMIN should be at least ctod(1) so that vtod() works.
 * vminit() insures this.
 */
#define	DMMIN	32			/* smallest swap allocation */
#define	DMMAX	4096			/* largest potential swap allocation */

/*
 * PTEs for mapping user space into the kernel for phyio operations.
 * [this figure is based on the assumption that you can put ptes in real
 *  memory.  this is a false assumption on a sun3]
 *  
 */
#ifndef USRIOSIZE
#define USRIOSIZE	1
#endif

/*
 * The time for a process to be blocked before being very swappable.
 * This is a number of seconds which the system takes as being a non-trivial
 * amount of real time.  You probably shouldn't change this;
 * it is used in subtle ways (fractions and multiples of it are, that is, like
 * half of a ``long time'', almost a long time, etc.)
 * It is related to human patience and other factors which don't really
 * change over time.
 */
#define	MAXSLP 		20

/*
 * A swapped in process is given a small amount of core without being bothered
 * by the page replacement algorithm.  Basically this says that if you are
 * swapped in you deserve some resources.  We protect the last SAFERSS
 * pages against paging and will just swap you out rather than paging you.
 * Note that each process has at least UPAGES+CLSIZE pages which are not
 * paged anyways (this is currently 8+2=10 pages or 5k bytes), so this
 * number just means a swapped in process is given around 25k bytes.
 * Just for fun: current memory prices are 4600$ a megabyte on VAX (4/22/81),
 * so we loan each swapped in process memory worth 100$, or just admit
 * that we don't consider it worthwhile and swap it out to disk which costs
 * $30/mb or about $0.75.
 */
#define	SAFERSS		4		/* nominal ``small'' resident set size
					   protected against replacement */


/*
 * Mach derived constants
 */

/* user/kernel map constants */
#define VM_MIN_ADDRESS		((vm_offset_t)0)
#define VM_MAXUSER_ADDRESS	((vm_offset_t)0x0E000000)
#define VM_MAX_ADDRESS		((vm_offset_t)0xFFF00000)
#define VM_MIN_KERNEL_ADDRESS	((vm_offset_t)0x0E004000)
#define VM_MAX_KERNEL_ADDRESS	((vm_offset_t)0x0FE00000) /* mon start */

/* virtual sizes (bytes) for various kernel submaps */
#define VM_MBUF_SIZE		(NMBCLUSTERS*MCLBYTES)
#define VM_KMEM_SIZE		(NKMEMCLUSTERS*CLBYTES)
#define VM_PHYS_SIZE		(USRIOSIZE*CLBYTES)