xref: /titanic_41/usr/src/uts/i86pc/sys/vm_machparam.h (revision ea394cb00fd96864e34d2841b4a22357b621c78f)
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