xref: /freebsd/sys/kern/subr_param.c (revision 23f282aa31e9b6fceacd449020e936e98d6f2298)
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  * $FreeBSD$
40  */
41 
42 #include <stddef.h>
43 
44 #include "opt_param.h"
45 
46 #include <sys/param.h>
47 
48 /*
49  * System parameter formulae.
50  *
51  * This file is copied into each directory where we compile
52  * the kernel; it should be modified there to suit local taste
53  * if necessary.
54  *
55  * Compiled with -DMAXUSERS=xx
56  */
57 
58 #ifndef HZ
59 #define	HZ 100
60 #endif
61 int	hz = HZ;
62 int	tick = 1000000 / HZ;
63 int	tickadj = howmany(30000, 60 * HZ);	/* can adjust 30ms in 60s */
64 #define	NPROC (20 + 16 * MAXUSERS)
65 #ifndef MAXFILES
66 #define MAXFILES (NPROC*2)
67 #endif
68 int	maxproc = NPROC;			/* maximum # of processes */
69 int	maxprocperuid = NPROC-1;		/* maximum # of processes per user */
70 int	maxfiles = MAXFILES;			/* system wide open files limit */
71 int	maxfilesperproc = MAXFILES;		/* per-process open files limit */
72 int	ncallout = 16 + NPROC + MAXFILES;	/* maximum # of timer events */
73 int	mbuf_wait = 32;				/* mbuf sleep time in ticks */
74 
75 /* maximum # of sf_bufs (sendfile(2) zero-copy virtual buffers) */
76 #ifndef NSFBUFS
77 #define	NSFBUFS (512 + MAXUSERS * 16)
78 #endif
79 int	nsfbufs = NSFBUFS;
80 
81 /*
82  * These may be set to nonzero here or by patching.
83  * If they are nonzero at bootstrap time then they are
84  * initialized to values dependent on the memory size.
85  */
86 #ifdef	NBUF
87 int	nbuf = NBUF;
88 #else
89 int	nbuf = 0;
90 #endif
91 int	nswbuf = 0;
92 
93 /*
94  * These have to be allocated somewhere; allocating
95  * them here forces loader errors if this file is omitted
96  * (if they've been externed everywhere else; hah!).
97  */
98 struct	buf *swbuf;
99