1*8df871f1Sbostic /*- 2*8df871f1Sbostic * Copyright (c) 1988 The Regents of the University of California. 3*8df871f1Sbostic * All rights reserved. 46ae514e1Skarels * 5*8df871f1Sbostic * This code is derived from software contributed to Berkeley by 6*8df871f1Sbostic * Computer Consoles Inc. 7*8df871f1Sbostic * 8*8df871f1Sbostic * %sccs.include.proprietary.c% 9*8df871f1Sbostic * 10*8df871f1Sbostic * @(#)vmparam.h 7.3 (Berkeley) 05/08/91 116ae514e1Skarels */ 12ddd4a425Ssam 13*8df871f1Sbostic /*- 1457e96b6cSsam * Machine dependent constants for tahoe. 15ddd4a425Ssam */ 1657e96b6cSsam 17ddd4a425Ssam /* 18ddd4a425Ssam * USRTEXT is the start of the user text/data space, while USRSTACK 19ddd4a425Ssam * is the top (end) of the user stack. LOWPAGES and HIGHPAGES are 20ddd4a425Ssam * the number of pages from the beginning of the P0 region to the 21ddd4a425Ssam * beginning of the text and from the beginning of the P2 region to the 22ddd4a425Ssam * beginning of the stack respectively. 23ddd4a425Ssam */ 24ddd4a425Ssam #define USRTEXT 0 250b8444b9Ssam #define USRSTACK (0xc0000000-UPAGES*NBPG) /* Start of user stack */ 260b8444b9Ssam #define BTOPUSRSTACK (0x300000 - UPAGES) /* btop(USRSTACK) */ 27ddd4a425Ssam #define P2PAGES 0x100000 /* number of pages in P2 region */ 28ddd4a425Ssam #define LOWPAGES 0 29ddd4a425Ssam #define HIGHPAGES UPAGES 30ddd4a425Ssam 31ddd4a425Ssam /* 32477ef2c3Ssam * Virtual memory related constants, all in bytes 33ddd4a425Ssam */ 34477ef2c3Ssam #define MAXTSIZ (6*1024*1024) /* max text size */ 350b8444b9Ssam #ifndef DFLDSIZ 36477ef2c3Ssam #define DFLDSIZ (6*1024*1024) /* initial data size limit */ 370b8444b9Ssam #endif 380b8444b9Ssam #ifndef MAXDSIZ 390f7249cfSsam #define MAXDSIZ (32*1024*1024) /* max data size */ 400b8444b9Ssam #endif 410b8444b9Ssam #ifndef DFLSSIZ 42477ef2c3Ssam #define DFLSSIZ (512*1024) /* initial stack size limit */ 430b8444b9Ssam #endif 440b8444b9Ssam #ifndef MAXSSIZ 450b8444b9Ssam #define MAXSSIZ MAXDSIZ /* max stack size */ 460b8444b9Ssam #endif 470b8444b9Ssam 480b8444b9Ssam /* 490b8444b9Ssam * Default sizes of swap allocation chunks (see dmap.h). 500b8444b9Ssam * The actual values may be changed in vminit() based on MAXDSIZ. 510b8444b9Ssam * With MAXDSIZ of 16Mb and NDMAP of 38, dmmax will be 1024. 52702aa092Smckusick * DMMIN should be at least ctod(1) so that vtod() works. 53702aa092Smckusick * vminit() ensures this. 540b8444b9Ssam */ 550b8444b9Ssam #define DMMIN 32 /* smallest swap allocation */ 560b8444b9Ssam #define DMMAX 4096 /* largest potential swap allocation */ 570b8444b9Ssam #define DMTEXT 1024 /* swap allocation for text */ 58ddd4a425Ssam 59ddd4a425Ssam /* 60ddd4a425Ssam * Sizes of the system and user portions of the system page table. 61ddd4a425Ssam */ 62ddd4a425Ssam /* SYSPTSIZE IS SILLY; IT SHOULD BE COMPUTED AT BOOT TIME */ 6345587f55Skarels #define SYSPTSIZE ((20+MAXUSERS/2)*NPTEPG) 640b8444b9Ssam #define USRPTSIZE (4*NPTEPG) 65ddd4a425Ssam 66ddd4a425Ssam /* 67702aa092Smckusick * PTEs for system V compatible shared memory. 68702aa092Smckusick * This is basically slop for kmempt which we actually allocate (malloc) from. 69702aa092Smckusick */ 70702aa092Smckusick #define SHMMAXPGS 512 71702aa092Smckusick 72702aa092Smckusick /* 73702aa092Smckusick * Boundary at which to place first MAPMEM segment if not explicitly 74702aa092Smckusick * specified. Should be a power of two. This allows some slop for 75702aa092Smckusick * the data segment to grow underneath the first mapped segment. 76702aa092Smckusick */ 77702aa092Smckusick #define MMSEG 0x200000 78702aa092Smckusick 79702aa092Smckusick /* 80ddd4a425Ssam * The size of the clock loop. 81ddd4a425Ssam */ 82ddd4a425Ssam #define LOOPPAGES (maxfree - firstfree) 83ddd4a425Ssam 84ddd4a425Ssam /* 85ddd4a425Ssam * The time for a process to be blocked before being very swappable. 86ddd4a425Ssam * This is a number of seconds which the system takes as being a non-trivial 87ddd4a425Ssam * amount of real time. You probably shouldn't change this; 88ddd4a425Ssam * it is used in subtle ways (fractions and multiples of it are, that is, like 89ddd4a425Ssam * half of a ``long time'', almost a long time, etc.) 90ddd4a425Ssam * It is related to human patience and other factors which don't really 91ddd4a425Ssam * change over time. 92ddd4a425Ssam */ 93ddd4a425Ssam #define MAXSLP 20 94ddd4a425Ssam 95ddd4a425Ssam /* 96ddd4a425Ssam * A swapped in process is given a small amount of core without being bothered 97ddd4a425Ssam * by the page replacement algorithm. Basically this says that if you are 98ddd4a425Ssam * swapped in you deserve some resources. We protect the last SAFERSS 99ddd4a425Ssam * pages against paging and will just swap you out rather than paging you. 100ddd4a425Ssam * Note that each process has at least UPAGES+CLSIZE pages which are not 101ddd4a425Ssam * paged anyways (this is currently 8+2=10 pages or 5k bytes), so this 102ddd4a425Ssam * number just means a swapped in process is given around 25k bytes. 103ddd4a425Ssam * Just for fun: current memory prices are 4600$ a megabyte on VAX (4/22/81), 104ddd4a425Ssam * so we loan each swapped in process memory worth 100$, or just admit 105ddd4a425Ssam * that we don't consider it worthwhile and swap it out to disk which costs 106ddd4a425Ssam * $30/mb or about $0.75. 107ddd4a425Ssam */ 1080b8444b9Ssam #define SAFERSS 32 /* nominal ``small'' resident set size 109ddd4a425Ssam protected against replacement */ 110ddd4a425Ssam 111ddd4a425Ssam /* 112ddd4a425Ssam * DISKRPM is used to estimate the number of paging i/o operations 113ddd4a425Ssam * which one can expect from a single disk controller. 114ddd4a425Ssam */ 115ddd4a425Ssam #define DISKRPM 60 116ddd4a425Ssam 117ddd4a425Ssam /* 118ddd4a425Ssam * Klustering constants. Klustering is the gathering 119ddd4a425Ssam * of pages together for pagein/pageout, while clustering 120ddd4a425Ssam * is the treatment of hardware page size as though it were 121ddd4a425Ssam * larger than it really is. 122ddd4a425Ssam * 123ddd4a425Ssam * KLMAX gives maximum cluster size in CLSIZE page (cluster-page) 124702aa092Smckusick * units. Note that ctod(KLMAX*CLSIZE) must be <= DMMIN in dmap.h. 125702aa092Smckusick * ctob(KLMAX) should also be less than MAXPHYS (in vm_swp.c) to 126702aa092Smckusick * avoid "big push" panics. 127ddd4a425Ssam */ 128ddd4a425Ssam 129ddd4a425Ssam #define KLMAX (32/CLSIZE) 130ddd4a425Ssam #define KLSEQL (16/CLSIZE) /* in klust if vadvise(VA_SEQL) */ 131ddd4a425Ssam #define KLIN (8/CLSIZE) /* default data/stack in klust */ 132ddd4a425Ssam #define KLTXT (4/CLSIZE) /* default text in klust */ 133ddd4a425Ssam #define KLOUT (32/CLSIZE) 134ddd4a425Ssam 135ddd4a425Ssam /* 136ddd4a425Ssam * KLSDIST is the advance or retard of the fifo reclaim for sequential 137ddd4a425Ssam * processes data space. 138ddd4a425Ssam */ 139ddd4a425Ssam #define KLSDIST 3 /* klusters advance/retard for seq. fifo */ 140ddd4a425Ssam 141ddd4a425Ssam /* 142ddd4a425Ssam * Paging thresholds (see vm_sched.c). 1430b8444b9Ssam * Strategy of 1/19/85: 1440b8444b9Ssam * lotsfree is 512k bytes, but at most 1/4 of memory 145ddd4a425Ssam * desfree is 200k bytes, but at most 1/8 of memory 146ddd4a425Ssam * minfree is 64k bytes, but at most 1/2 of desfree 147ddd4a425Ssam */ 1480b8444b9Ssam #define LOTSFREE (512 * 1024) 149ddd4a425Ssam #define LOTSFREEFRACT 4 150ddd4a425Ssam #define DESFREE (200 * 1024) 151ddd4a425Ssam #define DESFREEFRACT 8 152ddd4a425Ssam #define MINFREE (64 * 1024) 153ddd4a425Ssam #define MINFREEFRACT 2 154ddd4a425Ssam 155ddd4a425Ssam /* 1560b8444b9Ssam * There are two clock hands, initially separated by HANDSPREAD bytes 1570b8444b9Ssam * (but at most all of user memory). The amount of time to reclaim 1580b8444b9Ssam * a page once the pageout process examines it increases with this 1590b8444b9Ssam * distance and decreases as the scan rate rises. 1600b8444b9Ssam */ 1610b8444b9Ssam #define HANDSPREAD (2 * 1024 * 1024) 1620b8444b9Ssam 1630b8444b9Ssam /* 1640b8444b9Ssam * The number of times per second to recompute the desired paging rate 1650b8444b9Ssam * and poke the pagedaemon. 1660b8444b9Ssam */ 1670b8444b9Ssam #define RATETOSCHEDPAGING 4 1680b8444b9Ssam 1690b8444b9Ssam /* 170ddd4a425Ssam * Believed threshold (in megabytes) for which interleaved 171ddd4a425Ssam * swapping area is desirable. 172ddd4a425Ssam */ 173ddd4a425Ssam #define LOTSOFMEM 2 174ddd4a425Ssam 175a1d503faSkarels #define mapin(pte, v, pfnum, prot) \ 176a1d503faSkarels (*(int *)(pte) = (pfnum) | (prot), mtpr(TBIS, v)) 1770b8444b9Ssam 1780b8444b9Ssam /* 1790b8444b9Ssam * Invalidate a cluster (optimized here for standard CLSIZE). 1800b8444b9Ssam */ 1810b8444b9Ssam #if CLSIZE == 1 1820b8444b9Ssam #define tbiscl(v) mtpr(TBIS, ptob(v)) 1830b8444b9Ssam #endif 184