xref: /original-bsd/sys/pmax/include/vmparam.h (revision e59fb703)
1 /*
2  * Copyright (c) 1988 University of Utah.
3  * Copyright (c) 1992 The Regents of the University of California.
4  * All rights reserved.
5  *
6  * This code is derived from software contributed to Berkeley by
7  * the Systems Programming Group of the University of Utah Computer
8  * Science Department and Ralph Campbell.
9  *
10  * %sccs.include.redist.c%
11  *
12  * from: Utah $Hdr: vmparam.h 1.16 91/01/18$
13  *
14  *	@(#)vmparam.h	7.1 (Berkeley) 01/07/92
15  */
16 
17 /*
18  * Machine dependent constants for DEC Station 3100.
19  */
20 /*
21  * USRTEXT is the start of the user text/data space, while USRSTACK
22  * is the top (end) of the user stack.  LOWPAGES and HIGHPAGES are
23  * the number of pages from the beginning of the P0 region to the
24  * beginning of the text and from the beginning of the P1 region to the
25  * beginning of the stack respectively.
26  */
27 #define	USRTEXT		0x00400000
28 #define	USRDATA		0x10000000
29 #define	USRSTACK	0x80000000	/* Start of user stack */
30 #define	BTOPUSRSTACK	0x80000		/* btop(USRSTACK) */
31 #define	LOWPAGES	0x00400
32 #define	MIDPAGES	0x10000
33 #define	HIGHPAGES	0
34 
35 /*
36  * Virtual memory related constants, all in bytes
37  */
38 #ifndef MAXTSIZ
39 #define	MAXTSIZ		(24*1024*1024)		/* max text size */
40 #endif
41 #ifndef DFLDSIZ
42 #define	DFLDSIZ		(32*1024*1024)		/* initial data size limit */
43 #endif
44 #ifndef MAXDSIZ
45 #define	MAXDSIZ		(32*1024*1024)		/* max data size */
46 #endif
47 #ifndef	DFLSSIZ
48 #define	DFLSSIZ		(1024*1024)		/* initial stack size limit */
49 #endif
50 #ifndef	MAXSSIZ
51 #define	MAXSSIZ		MAXDSIZ			/* max stack size */
52 #endif
53 
54 /*
55  * Default sizes of swap allocation chunks (see dmap.h).
56  * The actual values may be changed in vminit() based on MAXDSIZ.
57  * With MAXDSIZ of 16Mb and NDMAP of 38, dmmax will be 1024.
58  * DMMIN should be at least ctod(1) so that vtod() works.
59  * vminit() insures this.
60  */
61 #define	DMMIN	32			/* smallest swap allocation */
62 #define	DMMAX	4096			/* largest potential swap allocation */
63 
64 /*
65  * Sizes of the system and user portions of the system page table.
66  */
67 /* SYSPTSIZE IS SILLY; (really number of buffers for I/O) */
68 #define	SYSPTSIZE	1228
69 #define	USRPTSIZE 	1024
70 
71 /*
72  * PTEs for mapping user space into the kernel for phyio operations.
73  * 16 pte's are enough to cover 8 disks * MAXBSIZE.
74  */
75 #ifndef USRIOSIZE
76 #define USRIOSIZE	32
77 #endif
78 
79 /*
80  * PTEs for system V style shared memory.
81  * This is basically slop for kmempt which we actually allocate (malloc) from.
82  */
83 #ifndef SHMMAXPGS
84 #define SHMMAXPGS	1024		/* 4mb */
85 #endif
86 
87 /*
88  * Boundary at which to place first MAPMEM segment if not explicitly
89  * specified.  Should be a power of two.  This allows some slop for
90  * the data segment to grow underneath the first mapped segment.
91  */
92 #define MMSEG		0x200000
93 
94 /*
95  * The size of the clock loop.
96  */
97 #define	LOOPPAGES	(maxfree - firstfree)
98 
99 /*
100  * The time for a process to be blocked before being very swappable.
101  * This is a number of seconds which the system takes as being a non-trivial
102  * amount of real time.  You probably shouldn't change this;
103  * it is used in subtle ways (fractions and multiples of it are, that is, like
104  * half of a ``long time'', almost a long time, etc.)
105  * It is related to human patience and other factors which don't really
106  * change over time.
107  */
108 #define	MAXSLP 		20
109 
110 /*
111  * A swapped in process is given a small amount of core without being bothered
112  * by the page replacement algorithm.  Basically this says that if you are
113  * swapped in you deserve some resources.  We protect the last SAFERSS
114  * pages against paging and will just swap you out rather than paging you.
115  * Note that each process has at least UPAGES+CLSIZE pages which are not
116  * paged anyways (this is currently 8+2=10 pages or 5k bytes), so this
117  * number just means a swapped in process is given around 25k bytes.
118  * Just for fun: current memory prices are 4600$ a megabyte on VAX (4/22/81),
119  * so we loan each swapped in process memory worth 100$, or just admit
120  * that we don't consider it worthwhile and swap it out to disk which costs
121  * $30/mb or about $0.75.
122  */
123 #define	SAFERSS		4		/* nominal ``small'' resident set size
124 					   protected against replacement */
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 #define	DISKRPM		60
131 
132 /*
133  * Klustering constants.  Klustering is the gathering
134  * of pages together for pagein/pageout, while clustering
135  * is the treatment of hardware page size as though it were
136  * larger than it really is.
137  *
138  * KLMAX gives maximum cluster size in CLSIZE page (cluster-page)
139  * units.  Note that ctod(KLMAX*CLSIZE) must be <= DMMIN in dmap.h.
140  * ctob(KLMAX) should also be less than MAXPHYS (in vm_swp.c)
141  * unless you like "big push" panics.
142  */
143 
144 #ifdef notdef /* XXX */
145 #define	KLMAX	(4/CLSIZE)
146 #define	KLSEQL	(2/CLSIZE)		/* in klust if vadvise(VA_SEQL) */
147 #define	KLIN	(4/CLSIZE)		/* default data/stack in klust */
148 #define	KLTXT	(4/CLSIZE)		/* default text in klust */
149 #define	KLOUT	(4/CLSIZE)
150 #else
151 #define	KLMAX	(1/CLSIZE)
152 #define	KLSEQL	(1/CLSIZE)
153 #define	KLIN	(1/CLSIZE)
154 #define	KLTXT	(1/CLSIZE)
155 #define	KLOUT	(1/CLSIZE)
156 #endif
157 
158 /*
159  * KLSDIST is the advance or retard of the fifo reclaim for sequential
160  * processes data space.
161  */
162 #define	KLSDIST	3		/* klusters advance/retard for seq. fifo */
163 
164 /*
165  * Paging thresholds (see vm_sched.c).
166  * Strategy of 1/19/85:
167  *	lotsfree is 512k bytes, but at most 1/4 of memory
168  *	desfree is 200k bytes, but at most 1/8 of memory
169  *	minfree is 64k bytes, but at most 1/2 of desfree
170  */
171 #define	LOTSFREE	(512 * 1024)
172 #define	LOTSFREEFRACT	4
173 #define	DESFREE		(200 * 1024)
174 #define	DESFREEFRACT	8
175 #define	MINFREE		(64 * 1024)
176 #define	MINFREEFRACT	2
177 
178 /*
179  * There are two clock hands, initially separated by HANDSPREAD bytes
180  * (but at most all of user memory).  The amount of time to reclaim
181  * a page once the pageout process examines it increases with this
182  * distance and decreases as the scan rate rises.
183  */
184 #define	HANDSPREAD	(2 * 1024 * 1024)
185 
186 /*
187  * The number of times per second to recompute the desired paging rate
188  * and poke the pagedaemon.
189  */
190 #define	RATETOSCHEDPAGING	4
191 
192 /*
193  * Believed threshold (in megabytes) for which interleaved
194  * swapping area is desirable.
195  */
196 #define	LOTSOFMEM	2
197 
198 #define	mapin(pte, v, pfnum, prot) \
199 	(*(int *)(pte) = ((pfnum) << PG_SHIFT) | (prot), MachTLBFlushAddr(v))
200 
201 /*
202  * Mach derived constants
203  */
204 
205 /* user/kernel map constants */
206 #define VM_MIN_ADDRESS		((vm_offset_t)0)
207 #define VM_MAXUSER_ADDRESS	((vm_offset_t)0x80000000)
208 #define VM_MAX_ADDRESS		((vm_offset_t)0x80000000)
209 #define VM_MIN_KERNEL_ADDRESS	((vm_offset_t)0xC0000000)
210 #define VM_MAX_KERNEL_ADDRESS	((vm_offset_t)0xFFFFC000)
211 
212 /* virtual sizes (bytes) for various kernel submaps */
213 #define VM_MBUF_SIZE		(NMBCLUSTERS*MCLBYTES)
214 #define VM_KMEM_SIZE		(NKMEMCLUSTERS*CLBYTES)
215 #define VM_PHYS_SIZE		(USRIOSIZE*CLBYTES)
216 
217 /* pcb base */
218 #define	pcbb(p)		((u_int)(p)->p_addr)
219