sys/kern/subr_param.c

   1 /*-
   2  * Copyright (c) 1980, 1986, 1989, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  * (c) UNIX System Laboratories, Inc.
   5  * All or some portions of this file are derived from material licensed
   6  * to the University of California by American Telephone and Telegraph
   7  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
   8  * the permission of UNIX System Laboratories, Inc.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 4. Neither the name of the University nor the names of its contributors
  19  *    may be used to endorse or promote products derived from this software
  20  *    without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  *      @(#)param.c     8.3 (Berkeley) 8/20/94
  35  */
  36
  37 #include <sys/cdefs.h>
  38 __FBSDID("$FreeBSD$");
  39
  40 #include "opt_param.h"
  41 #include "opt_maxusers.h"
  42
  43 #include <sys/param.h>
  44 #include <sys/systm.h>
  45 #include <sys/kernel.h>
  46 #include <sys/sysctl.h>
  47
  48 #include <vm/vm_param.h>
  49
  50 /*
  51  * System parameter formulae.
  52  */
  53
  54 #ifndef HZ
  55 #  if defined(__amd64__) || defined(__i386__) || defined(__ia64__) || defined(__sparc64__)
  56 #    define     HZ 1000
  57 #  else
  58 #    define     HZ 100
  59 #  endif
  60 #endif
  61 #define NPROC (20 + 16 * maxusers)
  62 #ifndef NBUF
  63 #define NBUF 0
  64 #endif
  65 #ifndef MAXFILES
  66 #define MAXFILES (maxproc * 2)
  67 #endif
  68
  69 int     hz;
  70 int     tick;
  71 int     maxusers;                       /* base tunable */
  72 int     maxproc;                        /* maximum # of processes */
  73 int     maxprocperuid;                  /* max # of procs per user */
  74 int     maxfiles;                       /* sys. wide open files limit */
  75 int     maxfilesperproc;                /* per-proc open files limit */
  76 int     ncallout;                       /* maximum # of timer events */
  77 int     nbuf;
  78 int     nswbuf;
  79 int     maxswzone;                      /* max swmeta KVA storage */
  80 int     maxbcache;                      /* max buffer cache KVA storage */
  81 int     maxpipekva;                     /* Limit on pipe KVA */
  82 u_long  maxtsiz;                        /* max text size */
  83 u_long  dfldsiz;                        /* initial data size limit */
  84 u_long  maxdsiz;                        /* max data size */
  85 u_long  dflssiz;                        /* initial stack size limit */
  86 u_long  maxssiz;                        /* max stack size */
  87 u_long  sgrowsiz;                       /* amount to grow stack */
  88
  89 SYSCTL_INT(_kern, OID_AUTO, hz, CTLFLAG_RDTUN, &hz, 0, "ticks/second");
  90 SYSCTL_INT(_kern, OID_AUTO, maxswzone, CTLFLAG_RDTUN, &maxswzone, 0,
  91     "max swmeta KVA storage");
  92 SYSCTL_INT(_kern, OID_AUTO, maxbcache, CTLFLAG_RDTUN, &maxbcache, 0,
  93     "max buffer cache KVA storage");
  94 SYSCTL_ULONG(_kern, OID_AUTO, maxtsiz, CTLFLAG_RDTUN, &maxtsiz, 0,
  95     "max text size");
  96 SYSCTL_ULONG(_kern, OID_AUTO, dfldsiz, CTLFLAG_RDTUN, &dfldsiz, 0,
  97     "initial data size limit");
  98 SYSCTL_ULONG(_kern, OID_AUTO, maxdsiz, CTLFLAG_RDTUN, &maxdsiz, 0,
  99     "max data size");
 100 SYSCTL_ULONG(_kern, OID_AUTO, dflssiz, CTLFLAG_RDTUN, &dflssiz, 0,
 101     "initial stack size limit");
 102 SYSCTL_ULONG(_kern, OID_AUTO, maxssiz, CTLFLAG_RDTUN, &maxssiz, 0,
 103     "max stack size");
 104 SYSCTL_ULONG(_kern, OID_AUTO, sgrowsiz, CTLFLAG_RDTUN, &sgrowsiz, 0,
 105     "amount to grow stack");
 106
 107 /*
 108  * These have to be allocated somewhere; allocating
 109  * them here forces loader errors if this file is omitted
 110  * (if they've been externed everywhere else; hah!).
 111  */
 112 struct  buf *swbuf;
 113
 114 /*
 115  * Boot time overrides that are not scaled against main memory
 116  */
 117 void
 118 init_param1(void)
 119 {
 120
 121         hz = HZ;
 122         TUNABLE_INT_FETCH("kern.hz", &hz);
 123         tick = 1000000 / hz;
 124
 125 #ifdef VM_SWZONE_SIZE_MAX
 126         maxswzone = VM_SWZONE_SIZE_MAX;
 127 #endif
 128         TUNABLE_INT_FETCH("kern.maxswzone", &maxswzone);
 129 #ifdef VM_BCACHE_SIZE_MAX
 130         maxbcache = VM_BCACHE_SIZE_MAX;
 131 #endif
 132         TUNABLE_INT_FETCH("kern.maxbcache", &maxbcache);
 133
 134         maxtsiz = MAXTSIZ;
 135         TUNABLE_ULONG_FETCH("kern.maxtsiz", &maxtsiz);
 136         dfldsiz = DFLDSIZ;
 137         TUNABLE_ULONG_FETCH("kern.dfldsiz", &dfldsiz);
 138         maxdsiz = MAXDSIZ;
 139         TUNABLE_ULONG_FETCH("kern.maxdsiz", &maxdsiz);
 140         dflssiz = DFLSSIZ;
 141         TUNABLE_ULONG_FETCH("kern.dflssiz", &dflssiz);
 142         maxssiz = MAXSSIZ;
 143         TUNABLE_ULONG_FETCH("kern.maxssiz", &maxssiz);
 144         sgrowsiz = SGROWSIZ;
 145         TUNABLE_ULONG_FETCH("kern.sgrowsiz", &sgrowsiz);
 146 }
 147
 148 /*
 149  * Boot time overrides that are scaled against main memory
 150  */
 151 void
 152 init_param2(long physpages)
 153 {
 154
 155         /* Base parameters */
 156         maxusers = MAXUSERS;
 157         TUNABLE_INT_FETCH("kern.maxusers", &maxusers);
 158         if (maxusers == 0) {
 159                 maxusers = physpages / (2 * 1024 * 1024 / PAGE_SIZE);
 160                 if (maxusers < 32)
 161                         maxusers = 32;
 162                 if (maxusers > 384)
 163                         maxusers = 384;
 164         }
 165
 166         /*
 167          * The following can be overridden after boot via sysctl.  Note:
 168          * unless overriden, these macros are ultimately based on maxusers.
 169          */
 170         maxproc = NPROC;
 171         TUNABLE_INT_FETCH("kern.maxproc", &maxproc);
 172         /*
 173          * Limit maxproc so that kmap entries cannot be exhausted by
 174          * processes.
 175          */
 176         if (maxproc > (physpages / 12))
 177                 maxproc = physpages / 12;
 178         maxfiles = MAXFILES;
 179         TUNABLE_INT_FETCH("kern.maxfiles", &maxfiles);
 180         maxprocperuid = (maxproc * 9) / 10;
 181         maxfilesperproc = (maxfiles * 9) / 10;
 182
 183         /*
 184          * Cannot be changed after boot.
 185          */
 186         nbuf = NBUF;
 187         TUNABLE_INT_FETCH("kern.nbuf", &nbuf);
 188
 189         ncallout = 16 + maxproc + maxfiles;
 190         TUNABLE_INT_FETCH("kern.ncallout", &ncallout);
 191 }
 192
 193 /*
 194  * Boot time overrides that are scaled against the kmem map
 195  */
 196 void
 197 init_param3(long kmempages)
 198 {
 199
 200         /*
 201          * The default for maxpipekva is max(5% of the kmem map, 512KB).
 202          * See sys_pipe.c for more details.
 203          */
 204         maxpipekva = (kmempages / 20) * PAGE_SIZE;
 205         if (maxpipekva < 512 * 1024)
 206                 maxpipekva = 512 * 1024;
 207         TUNABLE_INT_FETCH("kern.ipc.maxpipekva", &maxpipekva);
 208 }