/* vmparam.h 4.10 81/04/24 */ /* * Machine dependent constants */ #define NPTEPG (NBPG/(sizeof (struct pte))) /* number of ptes per page */ #define USRSTACK (0x80000000-UPAGES*NBPG) /* Start of user stack */ #define P1TOP 0x200000 /* boundary between P0 and P1 regions */ /* * Virtual memory related constants */ #define SLOP 32 #define MAXTSIZ (6*2048-SLOP) /* max text size (clicks) */ #define MAXDSIZ (12*1024-32-SLOP) /* max data size (clicks) */ #define MAXSSIZ (12*1024-32-SLOP) /* max stack size (clicks) */ /* * Sizes of the system and user portions of the system page table. */ /* SYSPTSIZE IS SILLY; IT SHOULD BE COMPUTED AT BOOT TIME */ #define SYSPTSIZE (12*NPTEPG) #define USRPTSIZE (8*NPTEPG) /* * The size of the clock loop. */ #define LOOPPAGES (maxfree - firstfree) /* * The time for a process to be blocked before being very swappable. * This is a number of seconds which the system takes as being a non-trivial * amount of real time. You probably shouldn't change this; * it is used in subtle ways (fractions and multiples of it are, that is, like * half of a ``long time'', almost a long time, etc.) * It is related to human patience and other factors which don't really * change over time. */ #define MAXSLP 20 /* * A swapped in process is given a small amount of core without being bothered * by the page replacement algorithm. Basically this says that if you are * swapped in you deserve some resources. We protect the last SAFERSS * pages against paging and will just swap you out rather than paging you. * Note that each process has at least UPAGES+CLSIZE pages which are not * paged anyways (this is currently 8+2=10 pages or 5k bytes), so this * number just means a swapped in process is given around 25k bytes. * Just for fun: current memory prices are 4600$ a megabyte on VAX (4/22/81), * so we loan each swapped in process memory worth 100$, or just admit * that we don't consider it worthwhile and swap it out to disk which costs * $30/mb or about $0.75. */ #define SAFERSS 32 /* nominal ``small'' resident set size protected against replacement */ /* * DISKRPM is used to estimate the number of paging i/o operations * which one can expect from a single disk controller. */ #define DISKRPM 60 /* * Klustering constants. Klustering is the gathering * of pages together for pagein/pageout, while clustering * is the treatment of hardware page size as though it were * larger than it really is. * * KLMAX gives maximum cluster size in CLSIZE page (cluster-page) * units. Note that KLMAX*CLSIZE must be <= DMMIN in dmap.h. */ #define KLMAX (32/CLSIZE) #define KLSEQL (16/CLSIZE) /* in klust if vadvise(VA_SEQL) */ #define KLIN (8/CLSIZE) /* default data/stack in klust */ #define KLTXT (4/CLSIZE) /* default text in klust */ #define KLOUT (32/CLSIZE) /* * KLSDIST is the advance or retard of the fifo reclaim for sequential * processes data space. */ #define KLSDIST 3 /* klusters advance/retard for seq. fifo */ #ifdef KERNEL int klseql; int klsdist; int klin; int kltxt; int klout; #endif