041be7d1f6e5dcee0cd94798aa04a1161ee54d16
/* vmparam.h 1.2 86/01/05 */
* Machine dependent constants for TAHOE
* USRTEXT is the start of the user text/data space, while USRSTACK
* is the top (end) of the user stack. LOWPAGES and HIGHPAGES are
* the number of pages from the beginning of the P0 region to the
* beginning of the text and from the beginning of the P2 region to the
* beginning of the stack respectively.
#define USRSTACK (0xc0000000-UPAGES*NBPG) /* Start of user stack */
#define BTOPUSRSTACK (0x300000 - UPAGES) /* btop(USRSTACK) */
#define P2PAGES 0x100000 /* number of pages in P2 region */
* Virtual memory related constants, all in clicks
#define MAXTSIZ (6*CLSIZE*1024) /* max text size */
#define DFLDSIZ (6*1024*1024/NBPG) /* initial data size limit */
#define MAXDSIZ (19*1024*1024/NBPG) /* max data size */
#define DFLSSIZ (512*1024/NBPG) /* initial stack size limit */
#define MAXSSIZ MAXDSIZ /* max stack size */
* Default sizes of swap allocation chunks (see dmap.h).
* The actual values may be changed in vminit() based on MAXDSIZ.
* With MAXDSIZ of 16Mb and NDMAP of 38, dmmax will be 1024.
#define DMMIN 32 /* smallest swap allocation */
#define DMMAX 4096 /* largest potential swap allocation */
#define DMTEXT 1024 /* swap allocation for text */
* Sizes of the system and user portions of the system page table.
/* SYSPTSIZE IS SILLY; IT SHOULD BE COMPUTED AT BOOT TIME */
#define SYSPTSIZE ((20+MAXUSERS)*NPTEPG)
#define USRPTSIZE (32*NPTEPG)
#define SYSPTSIZE ((128*NPTEPG/2)+(MAXUSERS*NPTEPG/16))
#define USRPTSIZE (4*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
* 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
#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.
* 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
#define KLSDIST 3 /* klusters advance/retard for seq. fifo */
* Paging thresholds (see vm_sched.c).
* lotsfree is 512k bytes, but at most 1/4 of memory
* desfree is 200k bytes, but at most 1/8 of memory
* minfree is 64k bytes, but at most 1/2 of desfree
#define LOTSFREE (512 * 1024)
#define DESFREE (200 * 1024)
#define MINFREE (64 * 1024)
* There are two clock hands, initially separated by HANDSPREAD bytes
* (but at most all of user memory). The amount of time to reclaim
* a page once the pageout process examines it increases with this
* distance and decreases as the scan rate rises.
#define HANDSPREAD (2 * 1024 * 1024)
* The number of times per second to recompute the desired paging rate
* and poke the pagedaemon.
#define RATETOSCHEDPAGING 4
* Believed threshold (in megabytes) for which interleaved
* swapping area is desirable.
* BEWARE THIS DEFINITION WORKS ONLY WITH COUNT OF 1
#define mapin(pte, v, pfnum, count, prot) \
(*(int *)(pte) = (pfnum) | (prot), mtpr(TBIS, ptob(v)))
* Invalidate a cluster (optimized here for standard CLSIZE).
#define tbiscl(v) mtpr(TBIS, ptob(v))
* The following constant is used to initialize the map of the
* system page table i/o entries.
* It's value should be the highest i/o address used by all the
* controllers handled in the system as specified in ubminit
#define MAXIOADDR 0xffffee45
/* number of entries in the system page pable for i/o space */
#define IOSIZE (((MAXIOADDR - (int)IOBASE+ NBPG-1) >> PGSHIFT)+1)
#define TBUFSIZ 32 /* maximum tape buffer size */
#define ACEBPTE 32 /* ACC Ethernet (ACE) I/O window */
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