xref: /freebsd/sys/kern/subr_param.c (revision af3b2549c4ba2ef00a7cbb4cb6836598bf0aefbe)
19454b2d8SWarner Losh /*-
2df8bae1dSRodney W. Grimes  * Copyright (c) 1980, 1986, 1989, 1993
3df8bae1dSRodney W. Grimes  *	The Regents of the University of California.  All rights reserved.
4df8bae1dSRodney W. Grimes  * (c) UNIX System Laboratories, Inc.
5df8bae1dSRodney W. Grimes  * All or some portions of this file are derived from material licensed
6df8bae1dSRodney W. Grimes  * to the University of California by American Telephone and Telegraph
7df8bae1dSRodney W. Grimes  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8df8bae1dSRodney W. Grimes  * the permission of UNIX System Laboratories, Inc.
9df8bae1dSRodney W. Grimes  *
10df8bae1dSRodney W. Grimes  * Redistribution and use in source and binary forms, with or without
11df8bae1dSRodney W. Grimes  * modification, are permitted provided that the following conditions
12df8bae1dSRodney W. Grimes  * are met:
13df8bae1dSRodney W. Grimes  * 1. Redistributions of source code must retain the above copyright
14df8bae1dSRodney W. Grimes  *    notice, this list of conditions and the following disclaimer.
15df8bae1dSRodney W. Grimes  * 2. Redistributions in binary form must reproduce the above copyright
16df8bae1dSRodney W. Grimes  *    notice, this list of conditions and the following disclaimer in the
17df8bae1dSRodney W. Grimes  *    documentation and/or other materials provided with the distribution.
18df8bae1dSRodney W. Grimes  * 4. Neither the name of the University nor the names of its contributors
19df8bae1dSRodney W. Grimes  *    may be used to endorse or promote products derived from this software
20df8bae1dSRodney W. Grimes  *    without specific prior written permission.
21df8bae1dSRodney W. Grimes  *
22df8bae1dSRodney W. Grimes  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23df8bae1dSRodney W. Grimes  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24df8bae1dSRodney W. Grimes  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25df8bae1dSRodney W. Grimes  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26df8bae1dSRodney W. Grimes  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27df8bae1dSRodney W. Grimes  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28df8bae1dSRodney W. Grimes  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29df8bae1dSRodney W. Grimes  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30df8bae1dSRodney W. Grimes  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31df8bae1dSRodney W. Grimes  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32df8bae1dSRodney W. Grimes  * SUCH DAMAGE.
33df8bae1dSRodney W. Grimes  *
3470b012caSJeffrey Hsu  *	@(#)param.c	8.3 (Berkeley) 8/20/94
35df8bae1dSRodney W. Grimes  */
36df8bae1dSRodney W. Grimes 
37677b542eSDavid E. O'Brien #include <sys/cdefs.h>
38677b542eSDavid E. O'Brien __FBSDID("$FreeBSD$");
39677b542eSDavid E. O'Brien 
404bd49128SPeter Wemm #include "opt_param.h"
414053b05bSSergey Kandaurov #include "opt_msgbuf.h"
42ee342e1bSPeter Wemm #include "opt_maxusers.h"
4350c73f36SGarrett Wollman 
44df8bae1dSRodney W. Grimes #include <sys/param.h>
45ee342e1bSPeter Wemm #include <sys/systm.h>
46ee342e1bSPeter Wemm #include <sys/kernel.h>
4702c6fc21SKonstantin Belousov #include <sys/limits.h>
484053b05bSSergey Kandaurov #include <sys/msgbuf.h>
4902c6fc21SKonstantin Belousov #include <sys/sysctl.h>
5002c6fc21SKonstantin Belousov #include <sys/proc.h>
51df8bae1dSRodney W. Grimes 
52e9a3f785SAlan Cox #include <vm/vm.h>
537419d1e2SDag-Erling Smørgrav #include <vm/vm_param.h>
54e9a3f785SAlan Cox #include <vm/pmap.h>
55cbc89bfbSPaul Saab 
56df8bae1dSRodney W. Grimes /*
57df8bae1dSRodney W. Grimes  * System parameter formulae.
58df8bae1dSRodney W. Grimes  */
59df8bae1dSRodney W. Grimes 
60df8bae1dSRodney W. Grimes #ifndef HZ
61bcebf6a1SNathan Whitehorn #  if defined(__mips__) || defined(__arm__)
62df8bae1dSRodney W. Grimes #    define	HZ 100
63bcebf6a1SNathan Whitehorn #  else
64bcebf6a1SNathan Whitehorn #    define	HZ 1000
65df8bae1dSRodney W. Grimes #  endif
667f03c419SMaxim Sobolev #  ifndef HZ_VM
67347e22a6SMike Silbersack #    define	HZ_VM 100
687f03c419SMaxim Sobolev #  endif
697f03c419SMaxim Sobolev #else
707f03c419SMaxim Sobolev #  ifndef HZ_VM
717f03c419SMaxim Sobolev #    define	HZ_VM HZ
727f03c419SMaxim Sobolev #  endif
738f650450SPeter Wemm #endif
74ee342e1bSPeter Wemm #define	NPROC (20 + 16 * maxusers)
75ee342e1bSPeter Wemm #ifndef NBUF
76ee342e1bSPeter Wemm #define NBUF 0
77ee342e1bSPeter Wemm #endif
785a00f364SDag-Erling Smørgrav #ifndef MAXFILES
79ee342e1bSPeter Wemm #define	MAXFILES (maxproc * 2)
805a00f364SDag-Erling Smørgrav #endif
81dd0b2081SDavid Greenman 
823610a226SIvan Voras static int sysctl_kern_vm_guest(SYSCTL_HANDLER_ARGS);
833610a226SIvan Voras 
845b999a6bSDavide Italiano int	hz;				/* system clock's frequency */
855b999a6bSDavide Italiano int	tick;				/* usec per tick (1000000 / hz) */
865b999a6bSDavide Italiano struct bintime tick_bt;			/* bintime per tick (1s / hz) */
875b999a6bSDavide Italiano sbintime_t tick_sbt;
88ee342e1bSPeter Wemm int	maxusers;			/* base tunable */
89ee342e1bSPeter Wemm int	maxproc;			/* maximum # of processes */
90ee342e1bSPeter Wemm int	maxprocperuid;			/* max # of procs per user */
91ee342e1bSPeter Wemm int	maxfiles;			/* sys. wide open files limit */
92ee342e1bSPeter Wemm int	maxfilesperproc;		/* per-proc open files limit */
934053b05bSSergey Kandaurov int	msgbufsize;			/* size of kernel message buffer */
94ee342e1bSPeter Wemm int	nbuf;
95ee75e7deSKonstantin Belousov int	bio_transient_maxcnt;
96412f9500SBrooks Davis int	ngroups_max;			/* max # groups per process */
97ee342e1bSPeter Wemm int	nswbuf;
9802c6fc21SKonstantin Belousov pid_t	pid_max = PID_MAX;
995bd65606SJohn Baldwin long	maxswzone;			/* max swmeta KVA storage */
1005bd65606SJohn Baldwin long	maxbcache;			/* max buffer cache KVA storage */
10164ecd139SJohn Baldwin long	maxpipekva;			/* Limit on pipe KVA */
1023dc30911SIvan Voras int 	vm_guest;			/* Running as virtual machine guest? */
1037419d1e2SDag-Erling Smørgrav u_long	maxtsiz;			/* max text size */
1047419d1e2SDag-Erling Smørgrav u_long	dfldsiz;			/* initial data size limit */
1057419d1e2SDag-Erling Smørgrav u_long	maxdsiz;			/* max data size */
1067419d1e2SDag-Erling Smørgrav u_long	dflssiz;			/* initial stack size limit */
1077419d1e2SDag-Erling Smørgrav u_long	maxssiz;			/* max stack size */
1087419d1e2SDag-Erling Smørgrav u_long	sgrowsiz;			/* amount to grow stack */
109df8bae1dSRodney W. Grimes 
110*af3b2549SHans Petter Selasky SYSCTL_INT(_kern, OID_AUTO, hz, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &hz, 0,
1119b84ba1cSJohn Baldwin     "Number of clock ticks per second");
112*af3b2549SHans Petter Selasky SYSCTL_INT(_kern, OID_AUTO, nbuf, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &nbuf, 0,
1139b84ba1cSJohn Baldwin     "Number of buffers in the buffer cache");
114*af3b2549SHans Petter Selasky SYSCTL_INT(_kern, OID_AUTO, nswbuf, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &nswbuf, 0,
115b9f2a7daSJohn Baldwin     "Number of swap buffers");
116*af3b2549SHans Petter Selasky SYSCTL_INT(_kern, OID_AUTO, msgbufsize, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &msgbufsize, 0,
1174053b05bSSergey Kandaurov     "Size of the kernel message buffer");
118*af3b2549SHans Petter Selasky SYSCTL_LONG(_kern, OID_AUTO, maxswzone, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &maxswzone, 0,
1199b84ba1cSJohn Baldwin     "Maximum memory for swap metadata");
120*af3b2549SHans Petter Selasky SYSCTL_LONG(_kern, OID_AUTO, maxbcache, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &maxbcache, 0,
1219b84ba1cSJohn Baldwin     "Maximum value of vfs.maxbufspace");
122*af3b2549SHans Petter Selasky SYSCTL_INT(_kern, OID_AUTO, bio_transient_maxcnt, CTLFLAG_RDTUN | CTLFLAG_NOFETCH,
123ee75e7deSKonstantin Belousov     &bio_transient_maxcnt, 0,
124ee75e7deSKonstantin Belousov     "Maximum number of transient BIOs mappings");
125*af3b2549SHans Petter Selasky SYSCTL_ULONG(_kern, OID_AUTO, maxtsiz, CTLFLAG_RWTUN | CTLFLAG_NOFETCH, &maxtsiz, 0,
1269b84ba1cSJohn Baldwin     "Maximum text size");
127*af3b2549SHans Petter Selasky SYSCTL_ULONG(_kern, OID_AUTO, dfldsiz, CTLFLAG_RWTUN | CTLFLAG_NOFETCH, &dfldsiz, 0,
1289b84ba1cSJohn Baldwin     "Initial data size limit");
129*af3b2549SHans Petter Selasky SYSCTL_ULONG(_kern, OID_AUTO, maxdsiz, CTLFLAG_RWTUN | CTLFLAG_NOFETCH, &maxdsiz, 0,
1309b84ba1cSJohn Baldwin     "Maximum data size");
131*af3b2549SHans Petter Selasky SYSCTL_ULONG(_kern, OID_AUTO, dflssiz, CTLFLAG_RWTUN | CTLFLAG_NOFETCH, &dflssiz, 0,
1329b84ba1cSJohn Baldwin     "Initial stack size limit");
133*af3b2549SHans Petter Selasky SYSCTL_ULONG(_kern, OID_AUTO, maxssiz, CTLFLAG_RWTUN | CTLFLAG_NOFETCH, &maxssiz, 0,
1349b84ba1cSJohn Baldwin     "Maximum stack size");
135*af3b2549SHans Petter Selasky SYSCTL_ULONG(_kern, OID_AUTO, sgrowsiz, CTLFLAG_RWTUN | CTLFLAG_NOFETCH, &sgrowsiz, 0,
136ceb0f715SAndrey Zonov     "Amount to grow stack on a stack fault");
1373610a226SIvan Voras SYSCTL_PROC(_kern, OID_AUTO, vm_guest, CTLFLAG_RD | CTLTYPE_STRING,
1383610a226SIvan Voras     NULL, 0, sysctl_kern_vm_guest, "A",
13907ce8d9bSIvan Voras     "Virtual machine guest detected? (none|generic|xen)");
1407c45a9c4SAlfred Perlstein 
141df8bae1dSRodney W. Grimes /*
142df8bae1dSRodney W. Grimes  * These have to be allocated somewhere; allocating
143df8bae1dSRodney W. Grimes  * them here forces loader errors if this file is omitted
144df8bae1dSRodney W. Grimes  * (if they've been externed everywhere else; hah!).
145df8bae1dSRodney W. Grimes  */
14628f8db14SBruce Evans struct	buf *swbuf;
1479722d88fSJason Evans 
1480b993ee5SAlan Cox /*
1490b993ee5SAlan Cox  * The elements of this array are ordered based upon the values of the
1500b993ee5SAlan Cox  * corresponding enum VM_GUEST members.
1510b993ee5SAlan Cox  */
15234820bbfSBjoern A. Zeeb static const char *const vm_guest_sysctl_names[] = {
15334820bbfSBjoern A. Zeeb 	"none",
15434820bbfSBjoern A. Zeeb 	"generic",
15534820bbfSBjoern A. Zeeb 	"xen",
15640b4cb0fSSergey Kandaurov 	"hv",
15734820bbfSBjoern A. Zeeb 	NULL
15834820bbfSBjoern A. Zeeb };
159903093ecSSergey Kandaurov CTASSERT(nitems(vm_guest_sysctl_names) - 1 == VM_LAST);
16034820bbfSBjoern A. Zeeb 
16134820bbfSBjoern A. Zeeb #ifndef XEN
1629bd2cbe4SJung-uk Kim static const char *const vm_bnames[] = {
1639bd2cbe4SJung-uk Kim 	"QEMU",				/* QEMU */
1649bd2cbe4SJung-uk Kim 	"Plex86",			/* Plex86 */
1659bd2cbe4SJung-uk Kim 	"Bochs",			/* Bochs */
166ea235a14SChristian S.J. Peron 	"Xen",				/* Xen */
167a09580e7SNeel Natu 	"BHYVE",			/* bhyve */
1680165f660SAndrey Zonov 	"Seabios",			/* KVM */
1699bd2cbe4SJung-uk Kim 	NULL
1709bd2cbe4SJung-uk Kim };
1719bd2cbe4SJung-uk Kim 
1724da059f3SMaxim Sobolev static const char *const vm_pnames[] = {
1737f03c419SMaxim Sobolev 	"VMware Virtual Platform",	/* VMWare VM */
1747f03c419SMaxim Sobolev 	"Virtual Machine",		/* Microsoft VirtualPC */
1757f03c419SMaxim Sobolev 	"VirtualBox",			/* Sun xVM VirtualBox */
1767f03c419SMaxim Sobolev 	"Parallels Virtual Platform",	/* Parallels VM */
1770165f660SAndrey Zonov 	"KVM",				/* KVM */
1787f03c419SMaxim Sobolev 	NULL
1797f03c419SMaxim Sobolev };
1807f03c419SMaxim Sobolev 
1813610a226SIvan Voras 
1823610a226SIvan Voras /*
1833610a226SIvan Voras  * Detect known Virtual Machine hosts by inspecting the emulated BIOS.
1843610a226SIvan Voras  */
1853dc30911SIvan Voras static enum VM_GUEST
1867f03c419SMaxim Sobolev detect_virtual(void)
1877f03c419SMaxim Sobolev {
1887f03c419SMaxim Sobolev 	char *sysenv;
1897f03c419SMaxim Sobolev 	int i;
1907f03c419SMaxim Sobolev 
1919bd2cbe4SJung-uk Kim 	sysenv = getenv("smbios.bios.vendor");
1929bd2cbe4SJung-uk Kim 	if (sysenv != NULL) {
1939bd2cbe4SJung-uk Kim 		for (i = 0; vm_bnames[i] != NULL; i++)
1949bd2cbe4SJung-uk Kim 			if (strcmp(sysenv, vm_bnames[i]) == 0) {
1959bd2cbe4SJung-uk Kim 				freeenv(sysenv);
1963dc30911SIvan Voras 				return (VM_GUEST_VM);
1979bd2cbe4SJung-uk Kim 			}
1989bd2cbe4SJung-uk Kim 		freeenv(sysenv);
1999bd2cbe4SJung-uk Kim 	}
2007f03c419SMaxim Sobolev 	sysenv = getenv("smbios.system.product");
2017f03c419SMaxim Sobolev 	if (sysenv != NULL) {
2029bd2cbe4SJung-uk Kim 		for (i = 0; vm_pnames[i] != NULL; i++)
2039bd2cbe4SJung-uk Kim 			if (strcmp(sysenv, vm_pnames[i]) == 0) {
2049bd2cbe4SJung-uk Kim 				freeenv(sysenv);
2053dc30911SIvan Voras 				return (VM_GUEST_VM);
2067f03c419SMaxim Sobolev 			}
2079bd2cbe4SJung-uk Kim 		freeenv(sysenv);
2087f03c419SMaxim Sobolev 	}
2093dc30911SIvan Voras 	return (VM_GUEST_NO);
2107f03c419SMaxim Sobolev }
21134820bbfSBjoern A. Zeeb #endif
2127f03c419SMaxim Sobolev 
2139722d88fSJason Evans /*
21466a11b9fSMatthew Dillon  * Boot time overrides that are not scaled against main memory
215ee342e1bSPeter Wemm  */
216ee342e1bSPeter Wemm void
21766a11b9fSMatthew Dillon init_param1(void)
218ee342e1bSPeter Wemm {
2193dc30911SIvan Voras #ifndef XEN
2203dc30911SIvan Voras 	vm_guest = detect_virtual();
2213dc30911SIvan Voras #else
2223dc30911SIvan Voras 	vm_guest = VM_GUEST_XEN;
2233dc30911SIvan Voras #endif
2247f03c419SMaxim Sobolev 	hz = -1;
225ee342e1bSPeter Wemm 	TUNABLE_INT_FETCH("kern.hz", &hz);
2269bd2cbe4SJung-uk Kim 	if (hz == -1)
2273dc30911SIvan Voras 		hz = vm_guest > VM_GUEST_NO ? HZ_VM : HZ;
228ee342e1bSPeter Wemm 	tick = 1000000 / hz;
2295b999a6bSDavide Italiano 	tick_sbt = SBT_1S / hz;
2305b999a6bSDavide Italiano 	tick_bt = sbttobt(tick_sbt);
231ee342e1bSPeter Wemm 
232e1616f3aSMatthew Dillon #ifdef VM_SWZONE_SIZE_MAX
2332f9e4e80SMatthew Dillon 	maxswzone = VM_SWZONE_SIZE_MAX;
234e1616f3aSMatthew Dillon #endif
2355bd65606SJohn Baldwin 	TUNABLE_LONG_FETCH("kern.maxswzone", &maxswzone);
236e1616f3aSMatthew Dillon #ifdef VM_BCACHE_SIZE_MAX
2372f9e4e80SMatthew Dillon 	maxbcache = VM_BCACHE_SIZE_MAX;
238e1616f3aSMatthew Dillon #endif
2395bd65606SJohn Baldwin 	TUNABLE_LONG_FETCH("kern.maxbcache", &maxbcache);
2404053b05bSSergey Kandaurov 	msgbufsize = MSGBUF_SIZE;
2414053b05bSSergey Kandaurov 	TUNABLE_INT_FETCH("kern.msgbufsize", &msgbufsize);
242cbc89bfbSPaul Saab 
243cbc89bfbSPaul Saab 	maxtsiz = MAXTSIZ;
2447419d1e2SDag-Erling Smørgrav 	TUNABLE_ULONG_FETCH("kern.maxtsiz", &maxtsiz);
245cbc89bfbSPaul Saab 	dfldsiz = DFLDSIZ;
2467419d1e2SDag-Erling Smørgrav 	TUNABLE_ULONG_FETCH("kern.dfldsiz", &dfldsiz);
247cbc89bfbSPaul Saab 	maxdsiz = MAXDSIZ;
2487419d1e2SDag-Erling Smørgrav 	TUNABLE_ULONG_FETCH("kern.maxdsiz", &maxdsiz);
249cbc89bfbSPaul Saab 	dflssiz = DFLSSIZ;
2507419d1e2SDag-Erling Smørgrav 	TUNABLE_ULONG_FETCH("kern.dflssiz", &dflssiz);
251cbc89bfbSPaul Saab 	maxssiz = MAXSSIZ;
2527419d1e2SDag-Erling Smørgrav 	TUNABLE_ULONG_FETCH("kern.maxssiz", &maxssiz);
253cbc89bfbSPaul Saab 	sgrowsiz = SGROWSIZ;
2547419d1e2SDag-Erling Smørgrav 	TUNABLE_ULONG_FETCH("kern.sgrowsiz", &sgrowsiz);
255412f9500SBrooks Davis 
256412f9500SBrooks Davis 	/*
257412f9500SBrooks Davis 	 * Let the administrator set {NGROUPS_MAX}, but disallow values
258412f9500SBrooks Davis 	 * less than NGROUPS_MAX which would violate POSIX.1-2008 or
259412f9500SBrooks Davis 	 * greater than INT_MAX-1 which would result in overflow.
260412f9500SBrooks Davis 	 */
261412f9500SBrooks Davis 	ngroups_max = NGROUPS_MAX;
262412f9500SBrooks Davis 	TUNABLE_INT_FETCH("kern.ngroups", &ngroups_max);
263412f9500SBrooks Davis 	if (ngroups_max < NGROUPS_MAX)
264412f9500SBrooks Davis 		ngroups_max = NGROUPS_MAX;
26502c6fc21SKonstantin Belousov 
26602c6fc21SKonstantin Belousov 	/*
26702c6fc21SKonstantin Belousov 	 * Only allow to lower the maximal pid.
2683fa615bcSKonstantin Belousov 	 * Prevent setting up a non-bootable system if pid_max is too low.
26902c6fc21SKonstantin Belousov 	 */
27002c6fc21SKonstantin Belousov 	TUNABLE_INT_FETCH("kern.pid_max", &pid_max);
27102c6fc21SKonstantin Belousov 	if (pid_max > PID_MAX)
27202c6fc21SKonstantin Belousov 		pid_max = PID_MAX;
2733fa615bcSKonstantin Belousov 	else if (pid_max < 300)
2743fa615bcSKonstantin Belousov 		pid_max = 300;
275ee75e7deSKonstantin Belousov 
276ee75e7deSKonstantin Belousov 	TUNABLE_INT_FETCH("vfs.unmapped_buf_allowed", &unmapped_buf_allowed);
277ee342e1bSPeter Wemm }
27866a11b9fSMatthew Dillon 
27966a11b9fSMatthew Dillon /*
28066a11b9fSMatthew Dillon  * Boot time overrides that are scaled against main memory
28166a11b9fSMatthew Dillon  */
28266a11b9fSMatthew Dillon void
283447b3772SPeter Wemm init_param2(long physpages)
28466a11b9fSMatthew Dillon {
28566a11b9fSMatthew Dillon 
28666a11b9fSMatthew Dillon 	/* Base parameters */
2870b94a0e9SMatthew Dillon 	maxusers = MAXUSERS;
2880b94a0e9SMatthew Dillon 	TUNABLE_INT_FETCH("kern.maxusers", &maxusers);
2890b94a0e9SMatthew Dillon 	if (maxusers == 0) {
2904fbd563eSMatthew Dillon 		maxusers = physpages / (2 * 1024 * 1024 / PAGE_SIZE);
29166a11b9fSMatthew Dillon 		if (maxusers < 32)
29266a11b9fSMatthew Dillon 			maxusers = 32;
29379f62ed6SAlfred Perlstein #ifdef VM_MAX_AUTOTUNE_MAXUSERS
29479f62ed6SAlfred Perlstein                 if (maxusers > VM_MAX_AUTOTUNE_MAXUSERS)
29579f62ed6SAlfred Perlstein                         maxusers = VM_MAX_AUTOTUNE_MAXUSERS;
29679f62ed6SAlfred Perlstein #endif
2977b6d92c0SAlfred Perlstein                 /*
29879f62ed6SAlfred Perlstein                  * Scales down the function in which maxusers grows once
29979f62ed6SAlfred Perlstein                  * we hit 384.
3007b6d92c0SAlfred Perlstein                  */
30179f62ed6SAlfred Perlstein                 if (maxusers > 384)
30279f62ed6SAlfred Perlstein                         maxusers = 384 + ((maxusers - 384) / 8);
30366a11b9fSMatthew Dillon         }
30466a11b9fSMatthew Dillon 
30566a11b9fSMatthew Dillon 	/*
30666a11b9fSMatthew Dillon 	 * The following can be overridden after boot via sysctl.  Note:
30766a11b9fSMatthew Dillon 	 * unless overriden, these macros are ultimately based on maxusers.
30877a7d074SMike Silbersack 	 * Limit maxproc so that kmap entries cannot be exhausted by
30977a7d074SMike Silbersack 	 * processes.
31077a7d074SMike Silbersack 	 */
311ead46972SAndre Oppermann 	maxproc = NPROC;
312ead46972SAndre Oppermann 	TUNABLE_INT_FETCH("kern.maxproc", &maxproc);
31377a7d074SMike Silbersack 	if (maxproc > (physpages / 12))
31477a7d074SMike Silbersack 		maxproc = physpages / 12;
315ebacce5eSMike Silbersack 	maxprocperuid = (maxproc * 9) / 10;
316ead46972SAndre Oppermann 
317ead46972SAndre Oppermann 	/*
318ead46972SAndre Oppermann 	 * The default limit for maxfiles is 1/12 of the number of
319ead46972SAndre Oppermann 	 * physical page but not less than 16 times maxusers.
320ead46972SAndre Oppermann 	 * At most it can be 1/6 the number of physical pages.
321ead46972SAndre Oppermann 	 */
322ead46972SAndre Oppermann 	maxfiles = imax(MAXFILES, physpages / 8);
323ead46972SAndre Oppermann 	TUNABLE_INT_FETCH("kern.maxfiles", &maxfiles);
324ead46972SAndre Oppermann 	if (maxfiles > (physpages / 4))
325ead46972SAndre Oppermann 		maxfiles = physpages / 4;
326ead46972SAndre Oppermann 	maxfilesperproc = (maxfiles / 10) * 9;
32766a11b9fSMatthew Dillon 
32866a11b9fSMatthew Dillon 	/*
329347194c1SMike Silbersack 	 * Cannot be changed after boot.
330347194c1SMike Silbersack 	 */
331347194c1SMike Silbersack 	nbuf = NBUF;
332347194c1SMike Silbersack 	TUNABLE_INT_FETCH("kern.nbuf", &nbuf);
333ee75e7deSKonstantin Belousov 	TUNABLE_INT_FETCH("kern.bio_transient_maxcnt", &bio_transient_maxcnt);
334347194c1SMike Silbersack 
335ead46972SAndre Oppermann 	/*
336e9a3f785SAlan Cox 	 * The default for maxpipekva is min(1/64 of the kernel address space,
337e9a3f785SAlan Cox 	 * max(1/64 of main memory, 512KB)).  See sys_pipe.c for more details.
338347194c1SMike Silbersack 	 */
339e9a3f785SAlan Cox 	maxpipekva = (physpages / 64) * PAGE_SIZE;
340ead46972SAndre Oppermann 	TUNABLE_LONG_FETCH("kern.ipc.maxpipekva", &maxpipekva);
341289016f2SMike Silbersack 	if (maxpipekva < 512 * 1024)
342289016f2SMike Silbersack 		maxpipekva = 512 * 1024;
343e9a3f785SAlan Cox 	if (maxpipekva > (VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS) / 64)
344e9a3f785SAlan Cox 		maxpipekva = (VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS) /
345e9a3f785SAlan Cox 		    64;
34666a11b9fSMatthew Dillon }
3473610a226SIvan Voras 
3483610a226SIvan Voras /*
34946038d7fSKonstantin Belousov  * Sysctl stringifying handler for kern.vm_guest.
3503610a226SIvan Voras  */
3513610a226SIvan Voras static int
3523610a226SIvan Voras sysctl_kern_vm_guest(SYSCTL_HANDLER_ARGS)
3533610a226SIvan Voras {
3543610a226SIvan Voras 	return (SYSCTL_OUT(req, vm_guest_sysctl_names[vm_guest],
3553610a226SIvan Voras 	    strlen(vm_guest_sysctl_names[vm_guest])));
3563610a226SIvan Voras }
357