1 /* $NetBSD: vmparam.h,v 1.22 1997/10/20 09:02:21 fvdl Exp $ */ 2 3 /*- 4 * Copyright (c) 1990 The Regents of the University of California. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * William Jolitz. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)vmparam.h 5.9 (Berkeley) 5/12/91 39 */ 40 41 42 /* 43 * Machine dependent constants for 386. 44 */ 45 46 /* 47 * Virtual address space arrangement. On 386, both user and kernel 48 * share the address space, not unlike the vax. 49 * USRTEXT is the start of the user text/data space, while USRSTACK 50 * is the top (end) of the user stack. Immediately above the user stack 51 * resides the user structure, which is UPAGES long and contains the 52 * kernel stack. 53 * 54 * Immediately after the user structure is the page table map, and then 55 * kernal address space. 56 */ 57 #define USRTEXT CLBYTES 58 #define USRSTACK VM_MAXUSER_ADDRESS 59 60 /* 61 * Virtual memory related constants, all in bytes 62 */ 63 #define MAXTSIZ (64*1024*1024) /* max text size */ 64 #ifndef DFLDSIZ 65 #define DFLDSIZ (128*1024*1024) /* initial data size limit */ 66 #endif 67 #ifndef MAXDSIZ 68 #define MAXDSIZ (1*1024*1024*1024) /* max data size */ 69 #endif 70 #ifndef DFLSSIZ 71 #define DFLSSIZ (2*1024*1024) /* initial stack size limit */ 72 #endif 73 #ifndef MAXSSIZ 74 #define MAXSSIZ (32*1024*1024) /* max stack size */ 75 #endif 76 77 /* 78 * Size of shared memory map 79 */ 80 #ifndef SHMMAXPGS 81 #define SHMMAXPGS 1024 82 #endif 83 84 /* 85 * Size of User Raw I/O map 86 */ 87 #define USRIOSIZE 300 88 89 /* 90 * The time for a process to be blocked before being very swappable. 91 * This is a number of seconds which the system takes as being a non-trivial 92 * amount of real time. You probably shouldn't change this; 93 * it is used in subtle ways (fractions and multiples of it are, that is, like 94 * half of a ``long time'', almost a long time, etc.) 95 * It is related to human patience and other factors which don't really 96 * change over time. 97 */ 98 #define MAXSLP 20 99 100 /* 101 * A swapped in process is given a small amount of core without being bothered 102 * by the page replacement algorithm. Basically this says that if you are 103 * swapped in you deserve some resources. We protect the last SAFERSS 104 * pages against paging and will just swap you out rather than paging you. 105 * Note that each process has at least UPAGES+CLSIZE pages which are not 106 * paged anyways (this is currently 8+2=10 pages or 5k bytes), so this 107 * number just means a swapped in process is given around 25k bytes. 108 * Just for fun: current memory prices are 4600$ a megabyte on VAX (4/22/81), 109 * so we loan each swapped in process memory worth 100$, or just admit 110 * that we don't consider it worthwhile and swap it out to disk which costs 111 * $30/mb or about $0.75. 112 * { wfj 6/16/89: Retail AT memory expansion $800/megabyte, loan of $17 113 * on disk costing $7/mb or $0.18 (in memory still 100:1 in cost!) } 114 * Update: memory prices have changed recently (9/96). At the current 115 * value of $6 per megabyte, we lend each swapped in process memory worth 116 * $0.15, or just admit that we don't consider it worthwhile and swap it out 117 * to disk which costs $0.20/MB, or just under half a cent. 118 */ 119 #define SAFERSS 8 /* nominal ``small'' resident set size 120 protected against replacement */ 121 122 /* 123 * Mach derived constants 124 */ 125 126 /* user/kernel map constants */ 127 #define VM_MIN_ADDRESS ((vm_offset_t)0) 128 /* PTDPTDI<<PDSHIFT - UPAGES*NBPG */ 129 #define VM_MAXUSER_ADDRESS ((vm_offset_t)0xefbfe000) 130 /* PTDPTDI<<PDSHIFT + PTDPTDI<<PGSHIFT */ 131 #define VM_MAX_ADDRESS ((vm_offset_t)0xeffbf000) 132 /* KPTDI<<PDSHIFT */ 133 #define VM_MIN_KERNEL_ADDRESS ((vm_offset_t)0xf0000000) 134 /* APTDPTDI<<PDSHIFT */ 135 #define VM_MAX_KERNEL_ADDRESS ((vm_offset_t)0xffc00000) 136 137 /* XXX max. amount of KVM to be used by buffers. */ 138 #ifndef VM_MAX_KERNEL_BUF 139 #define VM_MAX_KERNEL_BUF \ 140 ((VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS) * 7 / 10) 141 #endif 142 143 /* virtual sizes (bytes) for various kernel submaps */ 144 #define VM_MBUF_SIZE (NMBCLUSTERS*MCLBYTES) 145 #define VM_KMEM_SIZE (NKMEMCLUSTERS*CLBYTES) 146 #define VM_PHYS_SIZE (USRIOSIZE*CLBYTES) 147 148 #define MACHINE_NONCONTIG /* VM <=> pmap interface modifier */ 149