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/* $NetBSD: config.h,v 1.2 1995/03/18 14:58:47 cgd Exp $ */
/*-
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* 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.
*
* @(#)config.h 8.2 (Berkeley) 4/22/94
*/
/*
* The first boot and super blocks are given in absolute disk addresses.
* The byte-offset forms are preferred, as they don't imply a sector size.
*/
#define BBSIZE 8192
#define SBSIZE 8192
/*
* The following two constants set the default block and fragment sizes.
* Both constants must be a power of 2 and meet the following constraints:
* MINBSIZE <= DESBLKSIZE <= MAXBSIZE
* sectorsize <= DESFRAGSIZE <= DESBLKSIZE
* DESBLKSIZE / DESFRAGSIZE <= 8
*/
#define DFL_FRAGSIZE 1024
#define DFL_BLKSIZE 8192
/*
* Cylinder groups may have up to many cylinders. The actual
* number used depends upon how much information can be stored
* on a single cylinder. The default is to use 16 cylinders
* per group.
*/
#define DESCPG 16 /* desired fs_cpg */
/*
* MINFREE gives the minimum acceptable percentage of file system
* blocks which may be free. If the freelist drops below this level
* only the superuser may continue to allocate blocks. This may
* be set to 0 if no reserve of free blocks is deemed necessary,
* however throughput drops by fifty percent if the file system
* is run at between 90% and 100% full; thus the default value of
* fs_minfree is 10%. With 10% free space, fragmentation is not a
* problem, so we choose to optimize for time.
*/
#define MINFREE 10
#define DEFAULTOPT FS_OPTTIME
/*
* Preference for optimization.
*/
#define FS_OPTTIME 0 /* minimize allocation time */
#define FS_OPTSPACE 1 /* minimize disk fragmentation */
/*
* ROTDELAY gives the minimum number of milliseconds to initiate
* another disk transfer on the same cylinder. It is used in
* determining the rotationally optimal layout for disk blocks
* within a file; the default of fs_rotdelay is 4ms.
*/
#define ROTDELAY 4
/*
* MAXCONTIG sets the default for the maximum number of blocks
* that may be allocated sequentially. Since UNIX drivers are
* not capable of scheduling multi-block transfers, this defaults
* to 1 (ie no contiguous blocks are allocated).
*/
#define MAXCONTIG 1
/*
* MAXBLKPG determines the maximum number of data blocks which are
* placed in a single cylinder group. The default is one indirect
* block worth of data blocks.
*/
#define MAXBLKPG(bsize) ((bsize) / sizeof(daddr_t))
/*
* Each file system has a number of inodes statically allocated.
* We allocate one inode slot per NFPI fragments, expecting this
* to be far more than we will ever need.
*/
#define NFPI 4
/*
* For each cylinder we keep track of the availability of blocks at different
* rotational positions, so that we can lay out the data to be picked
* up with minimum rotational latency. NRPOS is the default number of
* rotational positions that we distinguish. With NRPOS of 8 the resolution
* of our summary information is 2ms for a typical 3600 rpm drive.
*/
#define NRPOS 8 /* number distinct rotational positions */
/*
* The following constants set the default block and segment size for a log
* structured file system. Both must be powers of two and the segment size
* must be a multiple of the block size. We also set minimum block and segment
* sizes.
*/
#define LFS_MINSEGSIZE (64*1024)
#define DFL_LFSSEG (1024 * 1024)
#define DFL_LFSSEG_SHIFT 20
#define DFL_LFSSEG_MASK 0xFFFFF
#define LFS_MINBLOCKSIZE 1024
#define DFL_LFSBLOCK 4096
#define DFL_LFSBLOCK_SHIFT 12
#define DFL_LFSBLOCK_MASK 0xFFF
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