date and time created 88/12/14 15:30:04 by sklower

[unix-history] / usr / src / sys / vm / vm_meter.c

diff --git a/usr/src/sys/vm/vm_meter.c b/usr/src/sys/vm/vm_meter.c
index addb677..9924dff 100644 (file)
--- a/usr/src/sys/vm/vm_meter.c
+++ b/usr/src/sys/vm/vm_meter.c
@@ -1,24 +1,44 @@
-/*     vm_meter.c      4.5     81/04/17        */
+/*
+ * Copyright (c) 1982, 1986 Regents of the University of California.
+ * All rights reserved.  The Berkeley software License Agreement
+ * specifies the terms and conditions for redistribution.
+ *
+ *     @(#)vm_meter.c  7.4 (Berkeley) %G%
+ */
+
+#include "param.h"
+#include "systm.h"
+#include "seg.h"
+#include "dir.h"
+#include "user.h"
+#include "proc.h"
+#include "text.h"
+#include "vm.h"
+#include "cmap.h"
+#include "kernel.h"
+

 
 

-#include "../h/param.h"
-#include "../h/systm.h"
-#include "../h/seg.h"
-#include "../h/dir.h"
-#include "../h/user.h"
-#include "../h/proc.h"
-#include "../h/text.h"
-#include "../h/vm.h"
-#include "../h/cmap.h"

 
 

-int    maxpgio = MAXPGIO;

 int    maxslp = MAXSLP;
 int    maxslp = MAXSLP;

-int    minfree = MINFREE;
-int    desfree = DESFREE;
-int    lotsfree = 0;           /* set to LOTSFREE in main unless adbed */

 int    saferss = SAFERSS;
 int    saferss = SAFERSS;

-int    slowscan = SLOWSCAN;
-int    fastscan = FASTSCAN;
+
+/*
+ * The following parameters control operation of the page replacement
+ * algorithm.  They are initialized to 0, and then computed at boot time
+ * based on the size of the system.  If they are patched non-zero in
+ * a loaded vmunix they are left alone and may thus be changed per system
+ * using adb on the loaded system.
+ */
+int    maxpgio = 0;
+int    minfree = 0;
+int    desfree = 0;
+int    lotsfree = 0;
+int    slowscan = 0;
+int    fastscan = 0;

 int    klin = KLIN;
 int    klin = KLIN;

+int    klseql = KLSEQL;
+int    klsdist = KLSDIST;
+int    kltxt = KLTXT;

 int    klout = KLOUT;
 int    multprog = -1;          /* so we don't count process 2 */
 
 int    klout = KLOUT;
 int    multprog = -1;          /* so we don't count process 2 */
 


@@ -71,21 +91,23 @@ sched()
        register struct bigp *bp, *nbp;
        int biggot, gives;
 
        register struct bigp *bp, *nbp;
        int biggot, gives;
 

-       /*
-        * Check if paging rate is too high, or average of
-        * free list very low and if so, adjust multiprogramming
-        * load by swapping someone out.
-        *
-        * Avoid glitches: don't hard swap the only process,
-        * and don't swap based on paging rate if there is a reasonable
-        * amount of free memory.
-        */

 loop:
        wantin = 0;
        deservin = 0;
        sleeper = 0;
        p = 0;
 loop:
        wantin = 0;
        deservin = 0;
        sleeper = 0;
        p = 0;

-       if (kmapwnt || (multprog > 1 && avefree < desfree &&
+       /*
+        * See if paging system is overloaded; if so swap someone out.
+        * Conditions for hard outswap are:
+        *      if need kernel map (mix it up).
+        * or
+        *      1. if there are at least 2 runnable processes (on the average)
+        * and  2. the paging rate is excessive or memory is now VERY low.
+        * and  3. the short (5-second) and longer (30-second) average
+        *         memory is less than desirable.
+        */
+       if (kmapwnt ||
+           (avenrun[0] >= 2 && imax(avefree, avefree30) < desfree &&

            (rate.v_pgin + rate.v_pgout > maxpgio || avefree < minfree))) {
                desperate = 1;
                goto hardswap;
            (rate.v_pgin + rate.v_pgout > maxpgio || avefree < minfree))) {
                desperate = 1;
                goto hardswap;


@@ -96,11 +118,12 @@ loop:
         * look for someone who deserves to be brought in.
         */
        outpri = -20000;
         * look for someone who deserves to be brought in.
         */
        outpri = -20000;

-       for (rp = proc; rp < procNPROC; rp++) switch(rp->p_stat) {
+       for (rp = allproc; rp != NULL; rp = rp->p_nxt) switch(rp->p_stat) {

 
        case SRUN:
                if ((rp->p_flag&SLOAD) == 0) {
 
        case SRUN:
                if ((rp->p_flag&SLOAD) == 0) {

-                       rppri = rp->p_time - rp->p_swrss / nz((maxpgio/2) * CLSIZE) +
+                       rppri = rp->p_time -
+                           rp->p_swrss / nz((maxpgio/2) * (klin * CLSIZE)) +

                            rp->p_slptime - (rp->p_nice-NZERO)*8;
                        if (rppri > outpri) {
                                if (rp->p_poip)
                            rp->p_slptime - (rp->p_nice-NZERO)*8;
                        if (rppri > outpri) {
                                if (rp->p_poip)


@@ -122,26 +145,20 @@ loop:
                        /*
                         * Kick out deadwood.
                         */
                        /*
                         * Kick out deadwood.
                         */

-                       (void) spl6();

                        rp->p_flag &= ~SLOAD;
                        rp->p_flag &= ~SLOAD;

-                       if (rp->p_stat == SRUN)
-                               remrq(rp);
-                       (void) spl0();

                        (void) swapout(rp, rp->p_dsize, rp->p_ssize);
                        (void) swapout(rp, rp->p_dsize, rp->p_ssize);

-                       goto loop;

                }
                continue;
        }
 
        /*
                }
                continue;
        }
 
        /*

-        * No one wants in, so nothing to do.
+        * If something came ready after we checked it,
+        * wantin will be set.  Otherwise,
+        * no one wants in, so nothing to do.

         */
        if (outpri == -20000) {
         */
        if (outpri == -20000) {

-               (void) spl6();
-               if (wantin) {
-                       wantin = 0;
-                       sleep((caddr_t)&lbolt, PSWP);
-               } else {
+               (void) splhigh();
+               if (wantin == 0) {

                        runout++;
                        sleep((caddr_t)&runout, PSWP);
                }
                        runout++;
                        sleep((caddr_t)&runout, PSWP);
                }


@@ -165,6 +182,7 @@ loop:
        needs = p->p_swrss;
        if (p->p_textp && p->p_textp->x_ccount == 0)
                needs += p->p_textp->x_swrss;
        needs = p->p_swrss;
        if (p->p_textp && p->p_textp->x_ccount == 0)
                needs += p->p_textp->x_swrss;

+       needs = imin(needs, lotsfree);

        if (freemem - deficit > needs / divisor) {
                deficit += needs;
                if (swapin(p))
        if (freemem - deficit > needs / divisor) {
                deficit += needs;
                if (swapin(p))


@@ -186,11 +204,9 @@ hardswap:
                nbig = 1;
        biggot = 0;
        bplist.bp_link = 0;
                nbig = 1;
        biggot = 0;
        bplist.bp_link = 0;

-       for (rp = proc; rp < procNPROC; rp++) {
+       for (rp = allproc; rp != NULL; rp = rp->p_nxt) {

                if (!swappable(rp))
                        continue;
                if (!swappable(rp))
                        continue;

-               if (rp->p_stat==SZOMB)
-                       continue;

                if (rp == inp)
                        continue;
                if (rp->p_textp && rp->p_textp->x_flag&XLOCK)
                if (rp == inp)
                        continue;
                if (rp->p_textp && rp->p_textp->x_flag&XLOCK)


@@ -242,7 +258,7 @@ hardswap:
         * we kick the poor luser out.
         */
        if (sleeper || desperate && p || deservin && inpri > maxslp) {
         * we kick the poor luser out.
         */
        if (sleeper || desperate && p || deservin && inpri > maxslp) {

-               (void) spl6();
+               (void) splhigh();

                p->p_flag &= ~SLOAD;
                if (p->p_stat == SRUN)
                        remrq(p);
                p->p_flag &= ~SLOAD;
                if (p->p_stat == SRUN)
                        remrq(p);


@@ -256,18 +272,20 @@ hardswap:
                        gives = p->p_rssize;
                        if (p->p_textp)
                                gives += p->p_textp->x_rssize / p->p_textp->x_ccount;
                        gives = p->p_rssize;
                        if (p->p_textp)
                                gives += p->p_textp->x_rssize / p->p_textp->x_ccount;

+                       gives = imin(gives, lotsfree);

                        deficit += gives;
                } else
                        gives = 0;      /* someone else taketh away */
                if (swapout(p, p->p_dsize, p->p_ssize) == 0)
                        deficit -= imin(gives, deficit);
                        deficit += gives;
                } else
                        gives = 0;      /* someone else taketh away */
                if (swapout(p, p->p_dsize, p->p_ssize) == 0)
                        deficit -= imin(gives, deficit);

-               goto loop;
+               else
+                       goto loop;

        }
        /*
         * Want to swap someone in, but can't
         * so wait on runin.
         */
        }
        /*
         * Want to swap someone in, but can't
         * so wait on runin.
         */

-       (void) spl6();
+       (void) splhigh();

        runin++;
        sleep((caddr_t)&runin, PSWP);
        (void) spl0();
        runin++;
        sleep((caddr_t)&runin, PSWP);
        (void) spl0();


@@ -278,8 +296,10 @@ vmmeter()
 {
        register unsigned *cp, *rp, *sp;
 
 {
        register unsigned *cp, *rp, *sp;
 

-       deficit -= imin(deficit, imax(deficit / 10, maxpgio / 2));
+       deficit -= imin(deficit,
+           imax(deficit / 10, ((klin * CLSIZE) / 2) * maxpgio / 2));

        ave(avefree, freemem, 5);
        ave(avefree, freemem, 5);

+       ave(avefree30, freemem, 30);

        /* v_pgin is maintained by clock.c */
        cp = &cnt.v_first; rp = &rate.v_first; sp = &sum.v_first;
        while (cp <= &cnt.v_last) {
        /* v_pgin is maintained by clock.c */
        cp = &cnt.v_first; rp = &rate.v_first; sp = &sum.v_first;
        while (cp <= &cnt.v_last) {


@@ -288,7 +308,7 @@ vmmeter()
                *cp = 0;
                rp++, cp++, sp++;
        }
                *cp = 0;
                rp++, cp++, sp++;
        }

-       if (time % 5 == 0) {
+       if (time.tv_sec % 5 == 0) {

                vmtotal();
                rate.v_swpin = cnt.v_swpin;
                sum.v_swpin += cnt.v_swpin;
                vmtotal();
                rate.v_swpin = cnt.v_swpin;
                sum.v_swpin += cnt.v_swpin;


@@ -305,32 +325,25 @@ vmmeter()
        }
 }
 
        }
 }
 

-vmpago()
+/*
+ * Schedule rate for paging.
+ * Rate is linear interpolation between
+ * slowscan with lotsfree and fastscan when out of memory.
+ */
+schedpaging()

 {
        register int vavail;
 {
        register int vavail;

-       register int scanrate;

 
 

-       /*
-        * Compute new rate for clock; if
-        * nonzero, restart clock.
-        * Rate ranges linearly from one rev per
-        * slowscan seconds when there is lotsfree memory
-        * available to one rev per fastscan seconds when
-        * there is no memory available.
-        */

        nscan = desscan = 0;
        vavail = freemem - deficit;
        if (vavail < 0)
                vavail = 0;
        nscan = desscan = 0;
        vavail = freemem - deficit;
        if (vavail < 0)
                vavail = 0;

-       if (freemem >= lotsfree)
-               return;
-       scanrate = (slowscan * vavail + fastscan * (lotsfree - vavail)) / nz(lotsfree);
-       desscan = LOOPSIZ / nz(scanrate);
-       /*
-        * DIVIDE BY 4 TO ACCOUNT FOR RUNNING 4* A SECOND (see clock.c)
-        */
-       desscan /= 4;
-       wakeup((caddr_t)&proc[2]);
+       if (freemem < lotsfree) {
+               desscan = (slowscan * vavail + fastscan * (lotsfree - vavail)) /
+                       nz(lotsfree) / RATETOSCHEDPAGING;
+               wakeup((caddr_t)&proc[2]);
+       }
+       timeout(schedpaging, (caddr_t)0, hz / RATETOSCHEDPAGING);

 }
 
 vmtotal()
 }
 
 vmtotal()


@@ -374,17 +387,19 @@ next:
        total.t_pw = 0;
        total.t_sl = 0;
        total.t_sw = 0;
        total.t_pw = 0;
        total.t_sl = 0;
        total.t_sw = 0;

-       for (p = proc; p < procNPROC; p++) {
+       for (p = allproc; p != NULL; p = p->p_nxt) {

                if (p->p_flag & SSYS)
                        continue;
                if (p->p_stat) {
                if (p->p_flag & SSYS)
                        continue;
                if (p->p_stat) {

-                       total.t_vm += p->p_dsize + p->p_ssize;
-                       total.t_rm += p->p_rssize;
+                       if (p->p_stat != SZOMB) {
+                               total.t_vm += p->p_dsize + p->p_ssize;
+                               total.t_rm += p->p_rssize;
+                       }

                        switch (p->p_stat) {
 
                        case SSLEEP:
                        case SSTOP:
                        switch (p->p_stat) {
 
                        case SSLEEP:
                        case SSTOP:

-                               if (p->p_pri <= PZERO)
+                               if (p->p_pri <= PZERO && p->p_stat == SSLEEP)

                                        nrun++;
                                if (p->p_flag & SPAGE)
                                        total.t_pw++;
                                        nrun++;
                                if (p->p_flag & SPAGE)
                                        total.t_pw++;