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      1 /*
      2  * CDDL HEADER START
      3  *
      4  * The contents of this file are subject to the terms of the
      5  * Common Development and Distribution License (the "License").
      6  * You may not use this file except in compliance with the License.
      7  *
      8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
      9  * or http://www.opensolaris.org/os/licensing.
     10  * See the License for the specific language governing permissions
     11  * and limitations under the License.
     12  *
     13  * When distributing Covered Code, include this CDDL HEADER in each
     14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
     15  * If applicable, add the following below this CDDL HEADER, with the
     16  * fields enclosed by brackets "[]" replaced with your own identifying
     17  * information: Portions Copyright [yyyy] [name of copyright owner]
     18  *
     19  * CDDL HEADER END
     20  */
     21 /*	Copyright (c) 1988 AT&T	*/
     22 /*	  All Rights Reserved  	*/
     23 /*
     24  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
     25  * Use is subject to license terms.
     26  */
     27 
     28 #ifndef _SYS_VM_MACHPARAM_H
     29 #define	_SYS_VM_MACHPARAM_H
     30 
     31 #pragma ident	"%Z%%M%	%I%	%E% SMI"
     32 
     33 #ifdef	__cplusplus
     34 extern "C" {
     35 #endif
     36 
     37 /*
     38  * Machine dependent constants for PC.
     39  */
     40 
     41 /*
     42  * USRTEXT is the start of the user text/data space.
     43  */
     44 #define	USRTEXT		USRSTACK
     45 
     46 /*
     47  * Virtual memory related constants for UNIX resource control, all in bytes.
     48  * The default stack size (initial stack size limit) keeps the stack from
     49  * taking more than 2 page directory entries in addition to the part of
     50  * the page directory entry which also maps the initial text and data,
     51  * and makes the default slightly bigger than the 8MB on SPARC.
     52  */
     53 #ifdef __amd64
     54 /*
     55  * On amd64, the stack grows down from just below KERNELBASE (see the
     56  * definition of USERLIMIT in i86pc/sys/machparam.h). Theoretically,
     57  * it could grow down to the top of the VA hole (0xffff800000000000),
     58  * giving it a possible maximum of about 125T. For an amd64 xpv
     59  * kernel, all user VA space is below the VA hole. The theoretical
     60  * maximum for the stack is about the same, although it can't grow
     61  * to quite that size, since it would clash with the heap.
     62  *
     63  * Pick an upper limit that will work in both cases: 32T.
     64  *
     65  * For 32bit processes, the stack is below the text segment.
     66  */
     67 #define	MAXSSIZ		(32ULL * 1024ULL * 1024ULL * 1024ULL * 1024ULL)
     68 #else
     69 #define	MAXSSIZ		(USRSTACK - 1024*1024)
     70 #endif /* __amd64 */
     71 #define	DFLSSIZ		(8*1024*1024 + ((USRSTACK) & 0x3FFFFF))
     72 
     73 /*
     74  * The following are limits beyond which the hard or soft limits for stack
     75  * and data cannot be increased. These may be viewed as fundamental
     76  * characteristics of the system. Note: a bug in SVVS requires that the
     77  * default hard limit be increasable, so the default hard limit must be
     78  * less than these physical limits.
     79  */
     80 #define	DSIZE_LIMIT	(USERLIMIT-USRTEXT)	/* physical data limit */
     81 #define	SSIZE_LIMIT	(USRSTACK)		/* physical stack limit */
     82 
     83 /*
     84  * Size of the kernel segkmem system pte table.  This virtual
     85  * space is controlled by the resource map "kernelmap".
     86  */
     87 #define	SYSPTSIZE	((61*1024*1024) / MMU_PAGESIZE)
     88 
     89 /*
     90  * Size of the ethernet addressable kernel segkmem system pte table.
     91  * This virtual space is controlled by the resource map "ekernelmap".
     92  * The ethernet interfaces in some sun machines can address only
     93  * the upper 16 Megabytes of memory.  Since the ethernet
     94  * driver kmem_allocs its memory, we bias all kmem_allocs
     95  * to try ekernelmap first and if it fails try kernelmap.
     96  * Folks that allocate directly out of kernelmap, above,
     97  * get memory that is non-ethernet addressable.
     98  */
     99 #define	E_SYSPTSIZE	(0x2000000 / MMU_PAGESIZE)
    100 
    101 /*
    102  * The virtual address space to be used by the seg_map segment
    103  * driver for fast kernel mappings.
    104  */
    105 #if defined(__i386)
    106 #define	SEGMAPDEFAULT	(16 * 1024 * 1024)
    107 #define	SEGMAPMAX	(128 * 1024 * 1024)
    108 #else
    109 #define	SEGMAPDEFAULT	(64 * 1024 * 1024)
    110 #endif
    111 
    112 /*
    113  * The time for a process to be blocked before being very swappable.
    114  * This is a number of seconds which the system takes as being a non-trivial
    115  * amount of real time. You probably shouldn't change this;
    116  * it is used in subtle ways (fractions and multiples of it are, that is, like
    117  * half of a ``long time'', almost a long time, etc.)
    118  * It is related to human patience and other factors which don't really
    119  * change over time.
    120  */
    121 #define	MAXSLP 		20
    122 
    123 /*
    124  * A swapped in process is given a small amount of core without being bothered
    125  * by the page replacement algorithm. Basically this says that if you are
    126  * swapped in you deserve some resources. We protect the last SAFERSS
    127  * pages against paging and will just swap you out rather than paging you.
    128  * Note that each process has at least UPAGES pages which are not
    129  * paged anyways so this number just means a swapped in process is
    130  * given around 32k bytes.
    131  */
    132 /*
    133  * nominal ``small'' resident set size
    134  * protected against replacement
    135  */
    136 #define	SAFERSS		3
    137 
    138 /*
    139  * DISKRPM is used to estimate the number of paging i/o operations
    140  * which one can expect from a single disk controller.
    141  *
    142  * XXX - The system doesn't account for multiple swap devices.
    143  */
    144 #define	DISKRPM		60
    145 
    146 /*
    147  * The maximum value for handspreadpages which is the the distance
    148  * between the two clock hands in pages.
    149  */
    150 #define	MAXHANDSPREADPAGES	((64 * 1024 * 1024) / PAGESIZE)
    151 
    152 /*
    153  * Paged text files that are less than PGTHRESH bytes
    154  * may be "prefaulted in" instead of demand paged.
    155  */
    156 #define	PGTHRESH	(280 * 1024)
    157 
    158 #ifdef	__cplusplus
    159 }
    160 #endif
    161 
    162 #endif	/* _SYS_VM_MACHPARAM_H */
    163