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freebsd/sys/kern/subr_param.c
David Greenman dd0b2081f4 Implemented zero-copy TCP/IP extensions via sendfile(2) - send a
file to a stream socket. sendfile(2) is similar to implementations in
HP-UX, Linux, and other systems, but the API is more extensive and
addresses many of the complaints that the Apache Group and others have
had with those other implementations. Thanks to Marc Slemko of the
Apache Group for helping me work out the best API for this.
Anyway, this has the "net" result of speeding up sends of files over
TCP/IP sockets by about 10X (that is to say, uses 1/10th of the CPU
cycles) when compared to a traditional read/write loop.
1998-11-05 14:28:26 +00:00

188 lines
5.8 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
* $Id: param.c,v 1.30 1998/07/11 13:06:38 bde Exp $
*/
#include "opt_sysvipc.h"
#include "opt_param.h"
#include <sys/param.h>
#ifdef SYSVSHM
#include <machine/vmparam.h>
#include <sys/shm.h>
#endif
#ifdef SYSVSEM
#include <sys/sem.h>
#endif
#ifdef SYSVMSG
#include <sys/msg.h>
#endif
/*
* System parameter formulae.
*
* This file is copied into each directory where we compile
* the kernel; it should be modified there to suit local taste
* if necessary.
*
* Compiled with -DMAXUSERS=xx
*/
#ifndef HZ
#define HZ 100
#endif
int hz = HZ;
int tick = 1000000 / HZ;
int tickadj = howmany(30000, 60 * HZ); /* can adjust 30ms in 60s */
#define NPROC (20 + 16 * MAXUSERS)
#define MAXFILES (NPROC*2)
int maxproc = NPROC; /* maximum # of processes */
int maxprocperuid = NPROC-1; /* maximum # of processes per user */
int maxfiles = MAXFILES; /* system wide open files limit */
int maxfilesperproc = MAXFILES; /* per-process open files limit */
int ncallout = 16 + NPROC + MAXFILES; /* maximum # of timer events */
/* maximum # of mbuf clusters */
#ifndef NMBCLUSTERS
#define NMBCLUSTERS (512 + MAXUSERS * 16)
#endif
int nmbclusters = NMBCLUSTERS;
#if MAXFILES > NMBCLUSTERS
#define MAXSOCKETS MAXFILES
#else
#define MAXSOCKETS NMBCLUSTERS
#endif
int maxsockets = MAXSOCKETS;
/* allocate 1/4th amount of virtual address space for mbufs XXX */
int nmbufs = NMBCLUSTERS * 4;
/* maximum # of sf_bufs (sendfile(2) zero-copy virtual buffers) */
#ifndef NSFBUFS
#define NSFBUFS (512 + MAXUSERS * 16)
#endif
int nsfbufs = NSFBUFS;
/*
* Values in support of System V compatible shared memory. XXX
*/
#ifdef SYSVSHM
#ifndef SHMMAX
#define SHMMAX (SHMMAXPGS*PAGE_SIZE)
#endif
#ifndef SHMMIN
#define SHMMIN 1
#endif
#ifndef SHMMNI
#define SHMMNI 32 /* <= SHMMMNI in shm.h */
#endif
#ifndef SHMSEG
#define SHMSEG 8
#endif
#ifndef SHMALL
#define SHMALL (SHMMAXPGS)
#endif
struct shminfo shminfo = {
SHMMAX,
SHMMIN,
SHMMNI,
SHMSEG,
SHMALL
};
#endif
/*
* Values in support of System V compatible semaphores.
*/
#ifdef SYSVSEM
struct seminfo seminfo = {
SEMMAP, /* # of entries in semaphore map */
SEMMNI, /* # of semaphore identifiers */
SEMMNS, /* # of semaphores in system */
SEMMNU, /* # of undo structures in system */
SEMMSL, /* max # of semaphores per id */
SEMOPM, /* max # of operations per semop call */
SEMUME, /* max # of undo entries per process */
SEMUSZ, /* size in bytes of undo structure */
SEMVMX, /* semaphore maximum value */
SEMAEM /* adjust on exit max value */
};
#endif
/*
* Values in support of System V compatible messages.
*/
#ifdef SYSVMSG
struct msginfo msginfo = {
MSGMAX, /* max chars in a message */
MSGMNI, /* # of message queue identifiers */
MSGMNB, /* max chars in a queue */
MSGTQL, /* max messages in system */
MSGSSZ, /* size of a message segment */
/* (must be small power of 2 greater than 4) */
MSGSEG /* number of message segments */
};
#endif
/*
* These may be set to nonzero here or by patching.
* If they are nonzero at bootstrap time then they are
* initialized to values dependent on the memory size.
*/
#ifdef NBUF
int nbuf = NBUF;
#else
int nbuf = 0;
#endif
int nswbuf = 0;
/*
* 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;