Commit Graph

101 Commits

Author SHA1 Message Date
Dima Dorfman
7ebcc426ef Remove whitespace at EOL. 2001-07-15 07:53:42 +00:00
Ruslan Ermilov
9fe48c6e8d mdoc(7) police: removed HISTORY info from the .Os call. 2001-07-10 11:04:34 +00:00
Dima Dorfman
70d51341bf mdoc(7) police: remove extraneous .Pp before and/or after .Sh. 2001-07-09 09:54:33 +00:00
Bruce Evans
e38c0bd643 Don't link ${BINDIR}/newfs to nowhere.
Don't clutter this Makefile (not to mention the error output) with
$(BDECFLAGS}.
2001-05-30 09:31:24 +00:00
Dima Dorfman
f628a4b10e Remove -DMFS from CFLAGS. 2001-05-29 23:57:23 +00:00
Dima Dorfman
7ccb741f6a Remove all references to MFS. 2001-05-29 23:55:43 +00:00
Poul-Henning Kamp
80f86e526b A more complete removal of MFS related code.
XXX: This program badly needs a style(9) + BDECFLAGS treatment.
2001-05-29 19:40:39 +00:00
Poul-Henning Kamp
a383ba34c2 Initial cleanout of MFS from newfs. More complete wash needed. 2001-05-29 18:52:39 +00:00
Kris Kennaway
1fef4cc97d sprintf() -> snprintf()
Partially submitted by:	"Andrew R. Reiter" <arr@watson.org>
Obtained from:	OpenBSD
2001-04-24 10:26:00 +00:00
Kris Kennaway
c3b1df1293 Add a missing argument to an error message format string. 2001-04-17 07:21:48 +00:00
Nik Clayton
044479f5ad Add information about the new options to newfs and tunefs which set the
expected average file size and number of files per directory.  Could do
with some fleshing out.
2001-04-10 10:36:44 +00:00
Kirk McKusick
a61ab64ac4 Directory layout preference improvements from Grigoriy Orlov <gluk@ptci.ru>.
His description of the problem and solution follow. My own tests show
speedups on typical filesystem intensive workloads of 5% to 12% which
is very impressive considering the small amount of code change involved.

------

  One day I noticed that some file operations run much faster on
small file systems then on big ones. I've looked at the ffs
algorithms, thought about them, and redesigned the dirpref algorithm.

  First I want to describe the results of my tests. These results are old
and I have improved the algorithm after these tests were done. Nevertheless
they show how big the perfomance speedup may be. I have done two file/directory
intensive tests on a two OpenBSD systems with old and new dirpref algorithm.
The first test is "tar -xzf ports.tar.gz", the second is "rm -rf ports".
The ports.tar.gz file is the ports collection from the OpenBSD 2.8 release.
It contains 6596 directories and 13868 files. The test systems are:

1. Celeron-450, 128Mb, two IDE drives, the system at wd0, file system for
   test is at wd1. Size of test file system is 8 Gb, number of cg=991,
   size of cg is 8m, block size = 8k, fragment size = 1k OpenBSD-current
   from Dec 2000 with BUFCACHEPERCENT=35

2. PIII-600, 128Mb, two IBM DTLA-307045 IDE drives at i815e, the system
   at wd0, file system for test is at wd1. Size of test file system is 40 Gb,
   number of cg=5324, size of cg is 8m, block size = 8k, fragment size = 1k
   OpenBSD-current from Dec 2000 with BUFCACHEPERCENT=50

You can get more info about the test systems and methods at:
http://www.ptci.ru/gluk/dirpref/old/dirpref.html

                              Test Results

             tar -xzf ports.tar.gz               rm -rf ports
  mode  old dirpref new dirpref speedup old dirprefnew dirpref speedup
                             First system
 normal     667         472      1.41       477        331       1.44
 async      285         144      1.98       130         14       9.29
 sync       768         616      1.25       477        334       1.43
 softdep    413         252      1.64       241         38       6.34
                             Second system
 normal     329         81       4.06       263.5       93.5     2.81
 async      302         25.7    11.75       112          2.26   49.56
 sync       281         57.0     4.93       263         90.5     2.9
 softdep    341         40.6     8.4        284          4.76   59.66

"old dirpref" and "new dirpref" columns give a test time in seconds.
speedup - speed increasement in times, ie. old dirpref / new dirpref.

------

Algorithm description

The old dirpref algorithm is described in comments:

/*
 * Find a cylinder to place a directory.
 *
 * The policy implemented by this algorithm is to select from
 * among those cylinder groups with above the average number of
 * free inodes, the one with the smallest number of directories.
 */

A new directory is allocated in a different cylinder groups than its
parent directory resulting in a directory tree that is spreaded across
all the cylinder groups. This spreading out results in a non-optimal
access to the directories and files. When we have a small filesystem
it is not a problem but when the filesystem is big then perfomance
degradation becomes very apparent.

What I mean by a big file system ?

  1. A big filesystem is a filesystem which occupy 20-30 or more percent
     of total drive space, i.e. first and last cylinder are physically
     located relatively far from each other.
  2. It has a relatively large number of cylinder groups, for example
     more cylinder groups than 50% of the buffers in the buffer cache.

The first results in long access times, while the second results in
many buffers being used by metadata operations. Such operations use
cylinder group blocks and on-disk inode blocks. The cylinder group
block (fs->fs_cblkno) contains struct cg, inode and block bit maps.
It is 2k in size for the default filesystem parameters. If new and
parent directories are located in different cylinder groups then the
system performs more input/output operations and uses more buffers.
On filesystems with many cylinder groups, lots of cache buffers are
used for metadata operations.

My solution for this problem is very simple. I allocate many directories
in one cylinder group. I also do some things, so that the new allocation
method does not cause excessive fragmentation and all directory inodes
will not be located at a location far from its file's inodes and data.
The algorithm is:
/*
 * Find a cylinder group to place a directory.
 *
 * The policy implemented by this algorithm is to allocate a
 * directory inode in the same cylinder group as its parent
 * directory, but also to reserve space for its files inodes
 * and data. Restrict the number of directories which may be
 * allocated one after another in the same cylinder group
 * without intervening allocation of files.
 *
 * If we allocate a first level directory then force allocation
 * in another cylinder group.
 */

  My early versions of dirpref give me a good results for a wide range of
file operations and different filesystem capacities except one case:
those applications that create their entire directory structure first
and only later fill this structure with files.

  My solution for such and similar cases is to limit a number of
directories which may be created one after another in the same cylinder
group without intervening file creations. For this purpose, I allocate
an array of counters at mount time. This array is linked to the superblock
fs->fs_contigdirs[cg]. Each time a directory is created the counter
increases and each time a file is created the counter decreases. A 60Gb
filesystem with 8mb/cg requires 10kb of memory for the counters array.

  The maxcontigdirs is a maximum number of directories which may be created
without an intervening file creation. I found in my tests that the best
performance occurs when I restrict the number of directories in one cylinder
group such that all its files may be located in the same cylinder group.
There may be some deterioration in performance if all the file inodes
are in the same cylinder group as its containing directory, but their
data partially resides in a different cylinder group. The maxcontigdirs
value is calculated to try to prevent this condition. Since there is
no way to know how many files and directories will be allocated later
I added two optimization parameters in superblock/tunefs. They are:

        int32_t  fs_avgfilesize;   /* expected average file size */
        int32_t  fs_avgfpdir;      /* expected # of files per directory */

These parameters have reasonable defaults but may be tweeked for special
uses of a filesystem. They are only necessary in rare cases like better
tuning a filesystem being used to store a squid cache.

I have been using this algorithm for about 3 months. I have done
a lot of testing on filesystems with different capacities, average
filesize, average number of files per directory, and so on. I think
this algorithm has no negative impact on filesystem perfomance. It
works better than the default one in all cases. The new dirpref
will greatly improve untarring/removing/coping of big directories,
decrease load on cvs servers and much more. The new dirpref doesn't
speedup a compilation process, but also doesn't slow it down.

Obtained from:	Grigoriy Orlov <gluk@ptci.ru>
2001-04-10 08:38:59 +00:00
Bruce Evans
5f98b5af89 Fixed style bugs in previous commit. 2001-04-03 09:35:36 +00:00
David E. O'Brien
8af4736afe Document the newfs.c rev 1.33 changing the default c/g from 16 to 22. 2001-04-02 22:48:54 +00:00
David E. O'Brien
991bf32193 Fix patch merge braino. 2001-04-02 22:46:02 +00:00
David E. O'Brien
b2cd1ce8ee Allow enabling soft updates (with -U) on a new filesystem.
[I first added this functionality, and thought to check prior art.  Seeing
OpenBSD had already done this, I changed my addition to reduce the diffs
between the two and went with their option letter.]
Obtained from:	OpenBSD
2001-04-02 01:25:55 +00:00
David E. O'Brien
094ab93715 The common wisdom is to use the largest number of cylinders per group.
So bump the default from `16' to `22', which is the largest value allowed
with the current default block size.  This change increases the the
group size from 32MB/g to 44MB/g on a 4GB SCSI disk.
2001-03-27 01:34:58 +00:00
Ruslan Ermilov
0a5779d45b - Backout botched attempt to introduce MANSECT feature.
- MAN[1-9] -> MAN.
2001-03-26 14:33:27 +00:00
Ruslan Ermilov
fe655281c5 Set the default manual section for sbin/ to 8. 2001-03-20 18:13:31 +00:00
Poul-Henning Kamp
7cf109c1b4 Make mount_mfs annoy users for 15 seconds and point them at mdconfig(8). 2001-01-30 10:21:20 +00:00
Ruslan Ermilov
9884911506 mdoc(7) police: fixed broken references. 2001-01-16 11:52:00 +00:00
Ian Dowse
f55ff3f3ef The ffs superblock includes a 128-byte region for use by temporary
in-core pointers to summary information. An array in this region
(fs_csp) could overflow on filesystems with a very large number of
cylinder groups (~16000 on i386 with 8k blocks). When this happens,
other fields in the superblock get corrupted, and fsck refuses to
check the filesystem.

Solve this problem by replacing the fs_csp array in 'struct fs'
with a single pointer, and add padding to keep the length of the
128-byte region fixed. Update the kernel and userland utilities
to use just this single pointer.

With this change, the kernel no longer makes use of the superblock
fields 'fs_csshift' and 'fs_csmask'. Add a comment to newfs/mkfs.c
to indicate that these fields must be calculated for compatibility
with older kernels.

Reviewed by:	mckusick
2001-01-15 18:30:40 +00:00
Eivind Eklund
10185bdc57 Replace reference to replacing mkfs(8) with a paragraph actually
describing what newfs *does*.
2001-01-15 03:13:26 +00:00
Ruslan Ermilov
d90d7015f9 Prepare for mdoc(7)NG. 2000-12-27 14:40:52 +00:00
Warner Losh
64dee60f8c o Add an example for a large file system.
o Remove bug about boot blocks hating non-8k file systems.  This hasn't been
  the case for a long time.

Not Objected to by: hackers, doc
2000-12-19 21:55:07 +00:00
Ruslan Ermilov
7c7fb079b9 mdoc(7) police: use the new features of the Nm macro. 2000-11-20 16:52:27 +00:00
Ruslan Ermilov
726b61ab5f Avoid use of direct troff requests in mdoc(7) manual pages. 2000-11-10 17:46:15 +00:00
John W. De Boskey
929f494bc7 Cast block number to off_t to avoid possible overflow bugs.
Pointed out by: Bruce Evans <bde@zeta.org.au>
2000-10-24 03:28:59 +00:00
John W. De Boskey
45c29d5cda The write combining code in revision 1.30 needs a few additional
touch ups.  The cache needs to be flushed against block
reads, and a final flush at process termination to force the
backup superblocks to disk.

I believe this will allow 'make release' to complete.

Submitted by:	Tor.Egge@fast.no
2000-10-24 00:08:30 +00:00
Peter Wemm
3927beeda1 Implement simple write combining for newfs - this is particularly useful
for large scsi disks with WCE = 0.  This yields around a 7 times speedup
on elapsed newfs time on test disks here.  64k clusters seems to be the
sweet spot for scsi disks using our present drivers.
2000-10-17 00:41:36 +00:00
Poul-Henning Kamp
fc87418be0 Turn dkcksum() into an __inline function.
Change its type to u_int_16_t.
2000-09-16 13:43:00 +00:00
Mike Smith
6801d96c70 Don't try to do anything with the /dev/rXXX device. 2000-05-31 01:00:51 +00:00
Sheldon Hearn
ef8f7ac935 Remove single-space hard sentence breaks. These degrade the quality
of the typeset output, tend to make diffs harder to read and provide
bad examples for new-comers to mdoc.
2000-03-01 11:27:47 +00:00
Kris Kennaway
d9d67bbaf8 Add Xref to camcontrol(8) (replacing previously-removed scsiformat(8)).
Submitted by:	joerg
2000-01-30 20:58:33 +00:00
Mike Pritchard
f050f700ad Fix various man pages to stop abusing the .Bx macro to generate
the strings "FreeBSD" and "NetBSD".  Use the .Fx or .Nx macro
instead.
2000-01-23 01:30:05 +00:00
Kris Kennaway
3c7fbe12d1 Remove dead xref to scsiformat(8)
Obtained from: OpenBSD (kind of)
1999-11-15 02:56:34 +00:00
Peter Wemm
7f3dea244c $Id$ -> $FreeBSD$ 1999-08-28 00:22:10 +00:00
Bill Fumerola
5682c39f91 Don't print a "," after the last superblock.
Submitted by:	adrian
1999-08-21 22:07:27 +00:00
Nick Hibma
de4a801355 Add again the ':' after the x option in th eargument list to getopt.
It disappeared in rev. 1.23 newfs.c

PR: 12292
Submitted by: Cy Schubert <cy@cschuber.net.gov.bc.ca>
1999-06-19 13:32:27 +00:00
Greg Lehey
63a134bc15 Describe the default values for useful options.
Clarify which options are no longer useful.
1999-03-10 21:59:02 +00:00
Matthew Dillon
cb84cdb1c4 Fix bug in mount_mfs whereby mount_mfs would sometimes return before
the mount is completely active, causing the next few commands attempting
    to manipulate data on the mount to fail.  mount_mfs's parent now tries
    to wait for the mount point st_dev to change before returning, indicating
    that the mount has gone active.
1999-02-09 17:19:19 +00:00
Bruce Evans
e14589db82 Straightened the terminology straightening in 1.17-1.18. Fixed hard
line breaks in rev.1.16-1.18.
1998-11-29 13:09:01 +00:00
Robert Nordier
c276ec5a07 Refer to "da" rather than "sd" device. 1998-11-28 10:02:52 +00:00
Bruce Evans
8116455e9d Backed out previous commit. It broke fsck again. See rev.1.22 and the
references there, and rev.1.38 of sys/ufs/ufs/ufs_disksubr.c.
1998-10-17 08:03:52 +00:00
Jordan K. Hubbard
7b955a8e5d Don't rewrite the disk label. The type field is already set correctly
and we don't use the frags info, so why bother?  More to the point, it
seems to result in an EXDEV error when the label is written out and we
lose because of it (don't know why though).  This is a work-around and
is marked as such.
1998-10-17 04:19:29 +00:00
Greg Lehey
e34129e8ba Correct source file corruption in last checkin
Observed by:  jkh
1998-09-30 07:53:52 +00:00
Greg Lehey
11ee80a991 Don't require an argument for -v flag
Correct checks for null special file names
Add Usage entry for -v flag
Get terminology straight in man page
Reviewed by:	bde
1998-09-29 23:20:04 +00:00
Greg Lehey
f7fb3ee05b Reviewed by: bde (again)
Correct terminology (partitions are in slices, not the other way around)
1998-09-11 07:08:49 +00:00
Greg Lehey
58343e4cc6 Reviewed by: bde,jkh
Add -v flag to newfs:

     -v      Specify that the partition does not contain any slices, and that
             newfs should treat the whole partition as the file system.  This
             option is useful for synthetic disks such as ccd and vinum.
1998-09-11 06:26:08 +00:00
Doug Rabson
48145dcdb4 Use explicitly sized types when formatting cylinder groups. 1998-08-27 07:38:33 +00:00