mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-22 11:17:19 +00:00
135 lines
5.1 KiB
C
135 lines
5.1 KiB
C
/*-
|
|
* 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
|