xref: /titanic_41/usr/src/uts/i86pc/sys/vm_machparam.h (revision cbca9407f17426a6bbd0fba98943cdb2f1cb6921)
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 #ifdef	__cplusplus
32 extern "C" {
33 #endif
34 
35 /*
36  * Machine dependent constants for PC.
37  */
38 
39 /*
40  * USRTEXT is the start of the user text/data space.
41  */
42 #define	USRTEXT		USRSTACK
43 
44 /*
45  * Virtual memory related constants for UNIX resource control, all in bytes.
46  * The default stack size (initial stack size limit) keeps the stack from
47  * taking more than 2 page directory entries in addition to the part of
48  * the page directory entry which also maps the initial text and data,
49  * and makes the default slightly bigger than the 8MB on SPARC.
50  */
51 #ifdef __amd64
52 /*
53  * On amd64, the stack grows down from just below KERNELBASE (see the
54  * definition of USERLIMIT in i86pc/sys/machparam.h). Theoretically,
55  * it could grow down to the top of the VA hole (0xffff800000000000),
56  * giving it a possible maximum of about 125T. For an amd64 xpv
57  * kernel, all user VA space is below the VA hole. The theoretical
58  * maximum for the stack is about the same, although it can't grow
59  * to quite that size, since it would clash with the heap.
60  *
61  * Pick an upper limit that will work in both cases: 32T.
62  *
63  * For 32bit processes, the stack is below the text segment.
64  */
65 #define	MAXSSIZ		(32ULL * 1024ULL * 1024ULL * 1024ULL * 1024ULL)
66 #else
67 #define	MAXSSIZ		(USRSTACK - 1024*1024)
68 #endif /* __amd64 */
69 #define	DFLSSIZ		(8*1024*1024 + ((USRSTACK) & 0x3FFFFF))
70 
71 /*
72  * Size of the kernel segkmem system pte table.  This virtual
73  * space is controlled by the resource map "kernelmap".
74  */
75 #define	SYSPTSIZE	((61*1024*1024) / MMU_PAGESIZE)
76 
77 /*
78  * Size of the ethernet addressable kernel segkmem system pte table.
79  * This virtual space is controlled by the resource map "ekernelmap".
80  * The ethernet interfaces in some sun machines can address only
81  * the upper 16 Megabytes of memory.  Since the ethernet
82  * driver kmem_allocs its memory, we bias all kmem_allocs
83  * to try ekernelmap first and if it fails try kernelmap.
84  * Folks that allocate directly out of kernelmap, above,
85  * get memory that is non-ethernet addressable.
86  */
87 #define	E_SYSPTSIZE	(0x2000000 / MMU_PAGESIZE)
88 
89 /*
90  * The virtual address space to be used by the seg_map segment
91  * driver for fast kernel mappings.
92  */
93 #if defined(__i386)
94 #define	SEGMAPDEFAULT	(16 * 1024 * 1024)
95 #define	SEGMAPMAX	(128 * 1024 * 1024)
96 #else
97 #define	SEGMAPDEFAULT	(64 * 1024 * 1024)
98 #endif
99 
100 /*
101  * The time for a process to be blocked before being very swappable.
102  * This is a number of seconds which the system takes as being a non-trivial
103  * amount of real time. You probably shouldn't change this;
104  * it is used in subtle ways (fractions and multiples of it are, that is, like
105  * half of a ``long time'', almost a long time, etc.)
106  * It is related to human patience and other factors which don't really
107  * change over time.
108  */
109 #define	MAXSLP 		20
110 
111 /*
112  * A swapped in process is given a small amount of core without being bothered
113  * by the page replacement algorithm. Basically this says that if you are
114  * swapped in you deserve some resources. We protect the last SAFERSS
115  * pages against paging and will just swap you out rather than paging you.
116  * Note that each process has at least UPAGES pages which are not
117  * paged anyways so this number just means a swapped in process is
118  * given around 32k bytes.
119  */
120 /*
121  * nominal ``small'' resident set size
122  * protected against replacement
123  */
124 #define	SAFERSS		3
125 
126 /*
127  * DISKRPM is used to estimate the number of paging i/o operations
128  * which one can expect from a single disk controller.
129  *
130  * XXX - The system doesn't account for multiple swap devices.
131  */
132 #define	DISKRPM		60
133 
134 /*
135  * The maximum value for handspreadpages which is the the distance
136  * between the two clock hands in pages.
137  */
138 #define	MAXHANDSPREADPAGES	((64 * 1024 * 1024) / PAGESIZE)
139 
140 /*
141  * Paged text files that are less than PGTHRESH bytes
142  * may be "prefaulted in" instead of demand paged.
143  */
144 #define	PGTHRESH	(280 * 1024)
145 
146 #ifdef	__cplusplus
147 }
148 #endif
149 
150 #endif	/* _SYS_VM_MACHPARAM_H */
151