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 * 2)
  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     tick;                           /* tick interval in microseconds */
  77 int     maxusers;                       /* base tunable */
  78 int     maxproc;                        /* maximum # of processes */
  79 int     maxprocperuid;                  /* max # of procs per user */
  80 int     maxfiles;                       /* system wide open files limit */
  81 int     maxfilesrootres;                /* descriptors reserved for root use */
  82 int     maxfilesperproc;                /* per-proc open files limit */
  83 int     maxposixlocksperuid;            /* max # POSIX locks per uid */
  84 int     ncallout;                       /* maximum # of timer events */
  85 int     mbuf_wait = 32;                 /* mbuf sleep time in ticks */
  86 int     nbuf;
  87 int     nswbuf;
  88 int     maxswzone;                      /* max swmeta KVA storage */
  89 int     maxbcache;                      /* max buffer cache KVA storage */
  90 u_quad_t        maxtsiz;                        /* max text size */
  91 u_quad_t        dfldsiz;                        /* initial data size limit */
  92 u_quad_t        maxdsiz;                        /* max data size */
  93 u_quad_t        dflssiz;                        /* initial stack size limit */
  94 u_quad_t        maxssiz;                        /* max stack size */
  95 u_quad_t        sgrowsiz;                       /* amount to grow stack */
  96
  97 /* maximum # of sf_bufs (sendfile(2) zero-copy virtual buffers) */
  98 int     nsfbufs;
  99
 100 /*
 101  * These have to be allocated somewhere; allocating
 102  * them here forces loader errors if this file is omitted
 103  * (if they've been externed everywhere else; hah!).
 104  */
 105 struct  buf *swbuf;
 106
 107 /*
 108  * Boot time overrides that are not scaled against main memory
 109  */
 110 void
 111 init_param1(void)
 112 {
 113         hz = HZ;
 114         TUNABLE_INT_FETCH("kern.hz", &hz);
 115         stathz = hz * 128 / 100;
 116         profhz = stathz;
 117         tick = 1000000 / hz;
 118         /* can adjust 30ms in 60s */
 119         ntp_default_tick_delta = howmany(30000000, 60 * hz);
 120
 121 #ifdef VM_SWZONE_SIZE_MAX
 122         maxswzone = VM_SWZONE_SIZE_MAX;
 123 #endif
 124         TUNABLE_INT_FETCH("kern.maxswzone", &maxswzone);
 125 #ifdef VM_BCACHE_SIZE_MAX
 126         maxbcache = VM_BCACHE_SIZE_MAX;
 127 #endif
 128         TUNABLE_INT_FETCH("kern.maxbcache", &maxbcache);
 129         maxtsiz = MAXTSIZ;
 130         TUNABLE_QUAD_FETCH("kern.maxtsiz", &maxtsiz);
 131         dfldsiz = DFLDSIZ;
 132         TUNABLE_QUAD_FETCH("kern.dfldsiz", &dfldsiz);
 133         maxdsiz = MAXDSIZ;
 134         TUNABLE_QUAD_FETCH("kern.maxdsiz", &maxdsiz);
 135         dflssiz = DFLSSIZ;
 136         TUNABLE_QUAD_FETCH("kern.dflssiz", &dflssiz);
 137         maxssiz = MAXSSIZ;
 138         TUNABLE_QUAD_FETCH("kern.maxssiz", &maxssiz);
 139         sgrowsiz = SGROWSIZ;
 140         TUNABLE_QUAD_FETCH("kern.sgrowsiz", &sgrowsiz);
 141 }
 142
 143 /*
 144  * Boot time overrides that are scaled against main memory
 145  */
 146 void
 147 init_param2(int physpages)
 148 {
 149
 150         /* Base parameters */
 151         maxusers = MAXUSERS;
 152         TUNABLE_INT_FETCH("kern.maxusers", &maxusers);
 153         if (maxusers == 0) {
 154                 maxusers = physpages / (2 * 1024 * 1024 / PAGE_SIZE);
 155                 if (maxusers < 32)
 156                     maxusers = 32;
 157                 if (maxusers > 384)
 158                     maxusers = 384;
 159         }
 160
 161         /*
 162          * The following can be overridden after boot via sysctl.  Note:
 163          * unless overriden, these macros are ultimately based on maxusers.
 164          */
 165         maxproc = NPROC;
 166         TUNABLE_INT_FETCH("kern.maxproc", &maxproc);
 167         /*
 168          * Limit maxproc so that kmap entries cannot be exhausted by
 169          * processes.
 170          */
 171         if (maxproc > (physpages / 12))
 172                 maxproc = physpages / 12;
 173         maxfiles = MAXFILES;
 174         TUNABLE_INT_FETCH("kern.maxfiles", &maxfiles);
 175         maxprocperuid = (maxproc * 9) / 10;
 176         maxfilesperproc = (maxfiles * 9) / 10;
 177         maxfilesrootres = maxfiles / 20;
 178
 179         maxposixlocksperuid = MAXPOSIXLOCKSPERUID;
 180         TUNABLE_INT_FETCH("kern.maxposixlocksperuid", &maxposixlocksperuid);
 181
 182         /*
 183          * Cannot be changed after boot.  Unless overriden, NSFBUFS is based
 184          * on maxusers and NBUF is typically 0 (auto-sized later).
 185          */
 186         nsfbufs = NSFBUFS;
 187         TUNABLE_INT_FETCH("kern.ipc.nsfbufs", &nsfbufs);
 188         nbuf = NBUF;
 189         TUNABLE_INT_FETCH("kern.nbuf", &nbuf);
 190
 191         ncallout = 16 + maxproc + maxfiles;
 192         TUNABLE_INT_FETCH("kern.ncallout", &ncallout);
 193 }
 194