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  * 3. All advertising materials mentioning features or use of this software
  19  *    must display the following acknowledgement:
  20  *      This product includes software developed by the University of
  21  *      California, Berkeley and its contributors.
  22  * 4. Neither the name of the University nor the names of its contributors
  23  *    may be used to endorse or promote products derived from this software
  24  *    without specific prior written permission.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  36  * SUCH DAMAGE.
  37  *
  38  *      @(#)param.c     8.3 (Berkeley) 8/20/94
  39  * $FreeBSD: src/sys/kern/subr_param.c,v 1.42.2.10 2002/03/09 21:05:47 silby Exp $
  40  * $DragonFly: src/sys/kern/subr_param.c,v 1.7 2005/06/26 22:03:22 dillon Exp $
  41  */
  42
  43 #include "opt_param.h"
  44 #include "opt_maxusers.h"
  45
  46 #include <sys/param.h>
  47 #include <sys/systm.h>
  48 #include <sys/kernel.h>
  49
  50 #include <machine/vmparam.h>
  51
  52 /*
  53  * System parameter formulae.
  54  */
  55
  56 #ifndef HZ
  57 #define HZ 100
  58 #endif
  59 #define NPROC (20 + 16 * maxusers)
  60 #ifndef NBUF
  61 #define NBUF 0
  62 #endif
  63 #ifndef MAXFILES
  64 #define MAXFILES (maxproc * 16)
  65 #endif
  66 #ifndef NSFBUFS
  67 #define NSFBUFS (512 + maxusers * 16)
  68 #endif
  69 #ifndef MAXPOSIXLOCKSPERUID
  70 #define MAXPOSIXLOCKSPERUID (maxusers * 64) /* Should be a safe value */
  71 #endif
  72
  73 int     hz;
  74 int     stathz;
  75 int     profhz;
  76 int     ustick;                         /* tick interval in microseconds */
  77 int     nstick;                         /* tick interval in nanoseconds */
  78 int     maxusers;                       /* base tunable */
  79 int     maxproc;                        /* maximum # of processes */
  80 int     maxprocperuid;                  /* max # of procs per user */
  81 int     maxfiles;                       /* system wide open files limit */
  82 int     maxfilesrootres;                /* descriptors reserved for root use */
  83 int     maxfilesperproc;                /* per-proc open files limit */
  84 int     maxposixlocksperuid;            /* max # POSIX locks per uid */
  85 int     ncallout;                       /* maximum # of timer events */
  86 int     mbuf_wait = 32;                 /* mbuf sleep time in ticks */
  87 int     nbuf;
  88 int     nswbuf;
  89 long    maxswzone;                      /* max swmeta KVA storage */
  90 long    maxbcache;                      /* max buffer cache KVA storage */
  91 u_quad_t        maxtsiz;                        /* max text size */
  92 u_quad_t        dfldsiz;                        /* initial data size limit */
  93 u_quad_t        maxdsiz;                        /* max data size */
  94 u_quad_t        dflssiz;                        /* initial stack size limit */
  95 u_quad_t        maxssiz;                        /* max stack size */
  96 u_quad_t        sgrowsiz;                       /* amount to grow stack */
  97
  98 /* maximum # of sf_bufs (sendfile(2) zero-copy virtual buffers) */
  99 int     nsfbufs;
 100
 101 /*
 102  * These have to be allocated somewhere; allocating
 103  * them here forces loader errors if this file is omitted
 104  * (if they've been externed everywhere else; hah!).
 105  */
 106 struct  buf *swbuf;
 107
 108 /*
 109  * Boot time overrides that are not scaled against main memory
 110  */
 111 void
 112 init_param1(void)
 113 {
 114         hz = HZ;
 115         TUNABLE_INT_FETCH("kern.hz", &hz);
 116         stathz = hz * 128 / 100;
 117         profhz = stathz;
 118         ustick = 1000000 / hz;
 119         nstick = 1000000000 / hz;
 120         /* can adjust 30ms in 60s */
 121         ntp_default_tick_delta = howmany(30000000, 60 * hz);
 122
 123 #ifdef VM_SWZONE_SIZE_MAX
 124         maxswzone = VM_SWZONE_SIZE_MAX;
 125 #endif
 126         TUNABLE_LONG_FETCH("kern.maxswzone", &maxswzone);
 127 #ifdef VM_BCACHE_SIZE_MAX
 128         maxbcache = VM_BCACHE_SIZE_MAX;
 129 #endif
 130         TUNABLE_LONG_FETCH("kern.maxbcache", &maxbcache);
 131         maxtsiz = MAXTSIZ;
 132         TUNABLE_QUAD_FETCH("kern.maxtsiz", &maxtsiz);
 133         dfldsiz = DFLDSIZ;
 134         TUNABLE_QUAD_FETCH("kern.dfldsiz", &dfldsiz);
 135         maxdsiz = MAXDSIZ;
 136         TUNABLE_QUAD_FETCH("kern.maxdsiz", &maxdsiz);
 137         dflssiz = DFLSSIZ;
 138         TUNABLE_QUAD_FETCH("kern.dflssiz", &dflssiz);
 139         maxssiz = MAXSSIZ;
 140         TUNABLE_QUAD_FETCH("kern.maxssiz", &maxssiz);
 141         sgrowsiz = SGROWSIZ;
 142         TUNABLE_QUAD_FETCH("kern.sgrowsiz", &sgrowsiz);
 143 }
 144
 145 /*
 146  * Boot time overrides that are scaled against main memory
 147  */
 148 void
 149 init_param2(int physpages)
 150 {
 151
 152         /* Base parameters */
 153         maxusers = MAXUSERS;
 154         TUNABLE_INT_FETCH("kern.maxusers", &maxusers);
 155         if (maxusers == 0) {
 156                 maxusers = physpages / (2 * 1024 * 1024 / PAGE_SIZE);
 157                 if (maxusers < 32)
 158                     maxusers = 32;
 159                 if (maxusers > 384)
 160                     maxusers = 384;
 161         }
 162
 163         /*
 164          * The following can be overridden after boot via sysctl.  Note:
 165          * unless overriden, these macros are ultimately based on maxusers.
 166          */
 167         maxproc = NPROC;
 168         TUNABLE_INT_FETCH("kern.maxproc", &maxproc);
 169         /*
 170          * Limit maxproc so that kmap entries cannot be exhausted by
 171          * processes.
 172          */
 173         if (maxproc > (physpages / 12))
 174                 maxproc = physpages / 12;
 175         maxfiles = MAXFILES;
 176         TUNABLE_INT_FETCH("kern.maxfiles", &maxfiles);
 177         maxprocperuid = (maxproc * 9) / 10;
 178         maxfilesperproc = (maxfiles * 9) / 10;
 179         maxfilesrootres = maxfiles / 20;
 180
 181         maxposixlocksperuid = MAXPOSIXLOCKSPERUID;
 182         TUNABLE_INT_FETCH("kern.maxposixlocksperuid", &maxposixlocksperuid);
 183
 184         /*
 185          * Cannot be changed after boot.  Unless overriden, NSFBUFS is based
 186          * on maxusers and NBUF is typically 0 (auto-sized later).
 187          */
 188         nsfbufs = NSFBUFS;
 189         TUNABLE_INT_FETCH("kern.ipc.nsfbufs", &nsfbufs);
 190         nbuf = NBUF;
 191         TUNABLE_INT_FETCH("kern.nbuf", &nbuf);
 192
 193         ncallout = 16 + maxproc + maxfiles;
 194         TUNABLE_INT_FETCH("kern.ncallout", &ncallout);
 195 }
 196