freebsd-dev/sys/kern/subr_param.c
Peter Wemm ee342e1bf1 Move param.c out of the conf directory and make it fully dynamic.
Tunables are now derived at boot time from maxusers.  ie: change maxusers
via a tunable and all the derivative settings change.  You can change
the other tunables individually as well.  Even hz etc is tunable.
2001-07-26 23:04:03 +00:00

120 lines
3.8 KiB
C

/*
* Copyright (c) 1980, 1986, 1989, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)param.c 8.3 (Berkeley) 8/20/94
* $FreeBSD$
*/
#include "opt_param.h"
#include "opt_maxusers.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
/*
* System parameter formulae.
*/
#ifndef HZ
#define HZ 100
#endif
#define NPROC (20 + 16 * maxusers)
#ifndef NBUF
#define NBUF 0
#endif
#ifndef MAXFILES
#define MAXFILES (maxproc * 2)
#endif
int hz;
int tick;
int tickadj; /* can adjust 30ms in 60s */
int maxusers; /* base tunable */
int maxproc; /* maximum # of processes */
int maxprocperuid; /* max # of procs per user */
int maxfiles; /* sys. wide open files limit */
int maxfilesperproc; /* per-proc open files limit */
int ncallout; /* maximum # of timer events */
int nbuf;
int nswbuf;
/*
* These have to be allocated somewhere; allocating
* them here forces loader errors if this file is omitted
* (if they've been externed everywhere else; hah!).
*/
struct buf *swbuf;
/*
* Total number of shared mutexes to protect all lockmgr locks.
*/
#ifndef LOCKMUTEX
#define LOCKMUTEX 10
#endif
int lock_nmtx = LOCKMUTEX;
/*
* Boot time overrides
*/
void
init_param(void)
{
/* Base parameters */
maxusers = MAXUSERS;
TUNABLE_INT_FETCH("kern.maxusers", &maxusers);
hz = HZ;
TUNABLE_INT_FETCH("kern.hz", &hz);
tick = 1000000 / hz;
tickadj = howmany(30000, 60 * hz); /* can adjust 30ms in 60s */
/* The following can be overridden after boot via sysctl */
maxproc = NPROC;
TUNABLE_INT_FETCH("kern.maxproc", &maxproc);
maxfiles = MAXFILES;
TUNABLE_INT_FETCH("kern.maxfiles", &maxfiles);
maxprocperuid = maxproc - 1;
maxfilesperproc = maxfiles;
/* Cannot be changed after boot */
nbuf = NBUF;
TUNABLE_INT_FETCH("kern.nbuf", &nbuf);
ncallout = 16 + maxproc + maxfiles;
TUNABLE_INT_FETCH("kern.ncallout", &ncallout);
}