subr_param.c revision 184326 
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: head/sys/kern/subr_param.c 184326 2008-10-27 08:09:05Z sobomax $");
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#  ifndef HZ_VM
61#    define	HZ_VM 10
62#  endif
63#else
64#  ifndef HZ_VM
65#    define	HZ_VM HZ
66#  endif
67#endif
68#define	NPROC (20 + 16 * maxusers)
69#ifndef NBUF
70#define NBUF 0
71#endif
72#ifndef MAXFILES
73#define	MAXFILES (maxproc * 2)
74#endif
75
76int	hz;
77int	tick;
78int	maxusers;			/* base tunable */
79int	maxproc;			/* maximum # of processes */
80int	maxprocperuid;			/* max # of procs per user */
81int	maxfiles;			/* sys. wide open files limit */
82int	maxfilesperproc;		/* per-proc open files limit */
83int	ncallout;			/* maximum # of timer events */
84int	nbuf;
85int	nswbuf;
86int	maxswzone;			/* max swmeta KVA storage */
87int	maxbcache;			/* max buffer cache KVA storage */
88int	maxpipekva;			/* Limit on pipe KVA */
89u_long	maxtsiz;			/* max text size */
90u_long	dfldsiz;			/* initial data size limit */
91u_long	maxdsiz;			/* max data size */
92u_long	dflssiz;			/* initial stack size limit */
93u_long	maxssiz;			/* max stack size */
94u_long	sgrowsiz;			/* amount to grow stack */
95
96SYSCTL_INT(_kern, OID_AUTO, hz, CTLFLAG_RDTUN, &hz, 0, "ticks/second");
97SYSCTL_INT(_kern, OID_AUTO, maxswzone, CTLFLAG_RDTUN, &maxswzone, 0,
98    "max swmeta KVA storage");
99SYSCTL_INT(_kern, OID_AUTO, maxbcache, CTLFLAG_RDTUN, &maxbcache, 0,
100    "max buffer cache KVA storage");
101SYSCTL_ULONG(_kern, OID_AUTO, maxtsiz, CTLFLAG_RDTUN, &maxtsiz, 0,
102    "max text size");
103SYSCTL_ULONG(_kern, OID_AUTO, dfldsiz, CTLFLAG_RDTUN, &dfldsiz, 0,
104    "initial data size limit");
105SYSCTL_ULONG(_kern, OID_AUTO, maxdsiz, CTLFLAG_RDTUN, &maxdsiz, 0,
106    "max data size");
107SYSCTL_ULONG(_kern, OID_AUTO, dflssiz, CTLFLAG_RDTUN, &dflssiz, 0,
108    "initial stack size limit");
109SYSCTL_ULONG(_kern, OID_AUTO, maxssiz, CTLFLAG_RDTUN, &maxssiz, 0,
110    "max stack size");
111SYSCTL_ULONG(_kern, OID_AUTO, sgrowsiz, CTLFLAG_RDTUN, &sgrowsiz, 0,
112    "amount to grow stack");
113
114/*
115 * These have to be allocated somewhere; allocating
116 * them here forces loader errors if this file is omitted
117 * (if they've been externed everywhere else; hah!).
118 */
119struct	buf *swbuf;
120
121static const char *const vm_pnames[] = {
122	"VMware Virtual Platform",	/* VMWare VM */
123	"Virtual Machine",		/* Microsoft VirtualPC */
124	"VirtualBox",			/* Sun xVM VirtualBox */
125	"Parallels Virtual Platform",	/* Parallels VM */
126	NULL
127};
128
129static int
130detect_virtual(void)
131{
132	char *sysenv;
133	int i;
134
135	sysenv = getenv("smbios.system.product");
136	if (sysenv != NULL) {
137		for (i = 0; vm_pnames[i] != NULL; i++) {
138			if (strcmp(sysenv, vm_pnames[i]) == 0)
139				return 1;
140		}
141	}
142	return 0;
143}
144
145/*
146 * Boot time overrides that are not scaled against main memory
147 */
148void
149init_param1(void)
150{
151
152	hz = -1;
153	TUNABLE_INT_FETCH("kern.hz", &hz);
154	if (hz == -1) {
155		if (detect_virtual()) {
156			hz = HZ_VM;
157		} else {
158			hz = HZ;
159		}
160	}
161	tick = 1000000 / hz;
162
163#ifdef VM_SWZONE_SIZE_MAX
164	maxswzone = VM_SWZONE_SIZE_MAX;
165#endif
166	TUNABLE_INT_FETCH("kern.maxswzone", &maxswzone);
167#ifdef VM_BCACHE_SIZE_MAX
168	maxbcache = VM_BCACHE_SIZE_MAX;
169#endif
170	TUNABLE_INT_FETCH("kern.maxbcache", &maxbcache);
171
172	maxtsiz = MAXTSIZ;
173	TUNABLE_ULONG_FETCH("kern.maxtsiz", &maxtsiz);
174	dfldsiz = DFLDSIZ;
175	TUNABLE_ULONG_FETCH("kern.dfldsiz", &dfldsiz);
176	maxdsiz = MAXDSIZ;
177	TUNABLE_ULONG_FETCH("kern.maxdsiz", &maxdsiz);
178	dflssiz = DFLSSIZ;
179	TUNABLE_ULONG_FETCH("kern.dflssiz", &dflssiz);
180	maxssiz = MAXSSIZ;
181	TUNABLE_ULONG_FETCH("kern.maxssiz", &maxssiz);
182	sgrowsiz = SGROWSIZ;
183	TUNABLE_ULONG_FETCH("kern.sgrowsiz", &sgrowsiz);
184}
185
186/*
187 * Boot time overrides that are scaled against main memory
188 */
189void
190init_param2(long physpages)
191{
192
193	/* Base parameters */
194	maxusers = MAXUSERS;
195	TUNABLE_INT_FETCH("kern.maxusers", &maxusers);
196	if (maxusers == 0) {
197		maxusers = physpages / (2 * 1024 * 1024 / PAGE_SIZE);
198		if (maxusers < 32)
199			maxusers = 32;
200		if (maxusers > 384)
201			maxusers = 384;
202	}
203
204	/*
205	 * The following can be overridden after boot via sysctl.  Note:
206	 * unless overriden, these macros are ultimately based on maxusers.
207	 */
208	maxproc = NPROC;
209	TUNABLE_INT_FETCH("kern.maxproc", &maxproc);
210	/*
211	 * Limit maxproc so that kmap entries cannot be exhausted by
212	 * processes.
213	 */
214	if (maxproc > (physpages / 12))
215		maxproc = physpages / 12;
216	maxfiles = MAXFILES;
217	TUNABLE_INT_FETCH("kern.maxfiles", &maxfiles);
218	maxprocperuid = (maxproc * 9) / 10;
219	maxfilesperproc = (maxfiles * 9) / 10;
220
221	/*
222	 * Cannot be changed after boot.
223	 */
224	nbuf = NBUF;
225	TUNABLE_INT_FETCH("kern.nbuf", &nbuf);
226
227	ncallout = 16 + maxproc + maxfiles;
228	TUNABLE_INT_FETCH("kern.ncallout", &ncallout);
229}
230
231/*
232 * Boot time overrides that are scaled against the kmem map
233 */
234void
235init_param3(long kmempages)
236{
237
238	/*
239	 * The default for maxpipekva is max(5% of the kmem map, 512KB).
240	 * See sys_pipe.c for more details.
241	 */
242	maxpipekva = (kmempages / 20) * PAGE_SIZE;
243	if (maxpipekva < 512 * 1024)
244		maxpipekva = 512 * 1024;
245	TUNABLE_INT_FETCH("kern.ipc.maxpipekva", &maxpipekva);
246}
247