File: AN-1.5a15

package info (click to toggle)
star 1.5a67-1
  • links: PTS
  • area: main
  • in suites: etch, etch-m68k
  • size: 5,600 kB
  • ctags: 4,715
  • sloc: ansic: 37,601; sh: 3,198; makefile: 200
file content (297 lines) | stat: -rw-r--r-- 11,214 bytes parent folder | download | duplicates (2)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
Newsgroups: comp.unix.admin,comp.unix.misc,alt.os.linux,alt.sys.sun,bln.comp.sun,bln.comp.unix,comp.os.linux.development.apps,comp.os.linux.misc,comp.sys.hp.apps,comp.sys.hp.misc,comp.sys.sgi.admin,comp.sys.sgi.apps,comp.sys.sgi.misc,comp.sys.sun.admin,comp.sys.sun.apps,comp.sys.sun.misc,comp.unix.aix,comp.unix.bsd.freebsd.misc,comp.unix.bsd.netbsd.misc,comp.unix.solaris,de.comp.os.linux.misc,de.comp.os.unix,linux.dev.admin,linux.dev.apps,maus.os.linux,maus.os.linux68k,maus.os.unix,uk.comp.os.linux
Subject: Star-1.5 source has been released

***************
Please have a look at the German open Source Center BerliOS at www.berlios.de
BerliOS will continue to support free hosting of cryptography projects even
when US laws change and don't allow to host cryptography projects in the USA.
Also look at sourcewell.berlios.de, the first Open Source announcement service
that itself is implemented as Open Source project.
***************

Star is the fastest tar archiver for UNIX

Star has many improvements compared to other tar 
implementations (including gnu tar). See below for a short description
of the highlight of star.

Star is located on:

ftp://ftp.berlios.de/pub/star

Changes since star-1.5.a14:

-	Removed option -I in preparation for using it in a different way
	in future releases.

-	Trying to make the source get accepted by 'cstyle'.

-	changed conf/cc-config.sh to check for a bad PATH set up
	(e.g. /usr/ucb before /opt/SUNWspro/bin) which would cause
	probems to use cc on Solaris.

-	Second fix from Andreas Gr´┐Żnbacher for #default comments
	in ACLs now also works correctly with multiple #default comments.

-	Warning: Environment STAR_FIFO_SIZE changed to STAR_FIFOSIZE
	This is to make star and cdrecord behave similar.

-	Star now reads a file /etc/default/star for default parameters.
	Currently implemented are:

	STAR_FIFOSIZE=
	and
	STAR_FIFOSIZE_MAX=

	STAR_FIFOSIZE= sets the FIFO size if no fs= option has been specified
	STAR_FIFOSIZE_MAX= limits the FIFO size even if a fs= option has been specified

-	Try to avoid that the verbose or diagnostic messages are
	sometimes lost if called on Linux via "ssh". Unfortunately,
	this does not always help. If you like to make sure that
	nothing gets lost, call: ssh host "star .... ; sleep 10"

		NOTE: The basic problem is caused ba a Linux bug


-	Star now opens a file that is going to be extracted with O_DSYNC.
	Thanks to a hint from Frank Batschulat from the Solaris filesystem
	kernel team.

	On operating systems with a decent buffer cache implementation
	(like Solaris), this speeds up extraction of many small or medium
	sizes files (e.g. a Linux kernel TAR archive) by approx. 20%
	On Linux, this change unfortunately is ineffective.


-	New option -no-fsync to avoid calling fsync(2) for each file
	if in extract mode.

	This helps to increase extraction speed on operating systems
	with badly implemented buffer cache (e.g. Linux).

	Note that using this option may be dangerous as star will not
	even be able to detect if a file could not be extracted correctly
	if it has been called with -no-fsync

	Backgound information:

	Calling fsync(2) in star's extract mode has been introduced in 1999.
	As star is developed on Solaris and on Solaris the performance degradation
	that is caused by calling fsync(2) is close to imperceptible, no 
	performance tests have been made for this feature until recently.

	A few weeks ago, some people reported that GNU tar is much faster
	than star when extracting files.

	Doing performance tests by extracting linux kernel TAR archives
	leads to the following results:

	-	Extration on Solaris without calling fsync(2) did speed up
		by ~ 40% compared to the standard case with calling fsync(2).

	-	After O_DSYNC has been introduced, the speed difference
		(compared to extraction without fsync) reduced to ~ 20%

		Extraction of a recent 2.4 Linux developer kernel archive
		took 50 seconds with star's default that calls fsync and
		42 seconds with star -no-fsync (56 seconds with star-1.5a14)

	-	On Linux (depending on filesystem type and disk type)
		extraction without calling fsync(2) is 3x to 8x faster
		than with the standard case that includes calling fsync.

	Star is develped for best possible data integrity while GNU tar
	does not seem to care about data integrity. The fact that GNU tar
	on Linux is much faster (for extraction) than star is no reason
	to blame star but a reason to blame the quality of the Linux
	buffer cache. Star will not change its default to a method that
	gives less data integrity just to speed up compared to GNU tar.

	The Solaris kernel is developed for best speed with guaranteed
	data integrity while the Linux kernel is developed for best speed
	without caring for data integrity. If you like that star will
	speed up in the star default (secure) mode, send a message to the
	Linux kernel developers team and request a change that gives a
	better behaviour of the Linux buffer cache.

-	New option level= # to set the current incremental dump level

-	New option tardumps=name to set file name for tar dump dates
	file. This file is similar to the file /etc/dumpdates that
	is manages by ufsdump.

-	New option -wtardumps to tell star update file for tar dump 
	dates if in dump mode.

	If you like to experiment with the new incremental dump features,
	you should start this way:

	Create a level 0 dump:

		star -cM -dump -sparse level=0 -wtardumps -C /usr .

	Create a level 1 dump:

		star -cM -dump -sparse level=1 -wtardumps -C /usr .

	If you do not have files that changed the type, no files that
	have been removed and no files that have been renamed,
	star would already be able to do incremental restores.


-	Better handling for the exitcode for star (needed for dump
	handling).

-	Allow 'smt' to understand that EACCES for read-only open may
	not be caused by a write protected tape but rather by access
	problems for a remote tape drive.

TODO:

-	Find a workaround for permission problems when extracting
	extended file flags (e.g. on BSD).



Revision history (short)

1982	First version on UNOS (extract only)
1985	Port to UNIX (fully functional version)
1985	Added pre Posix method of handling special files/devices
1986	First experiments with fifo as external process.
1993	Remote tape access
1993	diff option
1994	Fifo with shared memory integrated into star
1994	Very long filenames and sparse files
1994	Gnutar and Ustar(Posix.1-1988) handling added
1994	Xstar format (extended Posix.1-1988) defined and introduced
1995	Ported to many platforms
1999	Support for Win32 (Cygwin)
1999	base 256 support to overcome limitation with octal fields
2001	Large file support
2001	Support for POSIX.1-2001 extended headers
2001	Support for ACLs in POSIX.1-2001 extended headers
2002	Support for extended file flags in POSIX.1-2001 extended headers
2002	Support for extended inode meta data and meta files
2003	Error control added to allow to selectively ignore error contitions

Supported platforms:

Virtually any! Known to work:

SunOS 4.x, Solaris (SunOS 5.x), Linux,
HP-UX, DG/UX, IRIX, AIX, FreeBSD, NetBSD, OpenBSD,
OSF-1, True-64, QNX, BeOS, Apollo Domain/OS, Next-STep, 
OS/2, SCO-openserver, SCO-unixware, Caldera OpenUnix,
Cygwin (Win32), Sony NewsOS,  BSDi (BSD/OS), QNX,
Apple Rhapsody, MacOS X, AmigaOS, GNU Hurd

Joerg

-------------------------------------------------------------
Star is the fastest known implementation of a tar archiver.
Star is able to make backups with far more than 10MB/s if the
disk and tape drive support such a speed. This is more than
double the speed that ufsdump will get.
In 1996, Ampex got 13.5 MB/s with their DLT tape drive which is a
modified professional digital video tape drive and not related
to Quantum's DLT type drives.
Ufsdump got a maximum speed of about 6MB/s with the same hardware.

Star development started 1982, the first complete implementation has 
been done in 1985. I never did my backups with other tools than star.

Its main advantages over other tar implementations are:

	fifo			- keeps the tape streaming.
				  This gives you faster backups than
				  you can achieve with ufsdump, if the
				  size of the filesystem is > 1 GByte.

	remote tape support	- a fast RMT implementation that has no
				  probems to saturate a 100 Mb/s network.

	accurate sparse files	- star is able to reproduce holes in sparse
				  files accurately if the OS includes 
				  the needed support functions. This is
				  currently true for Solaris-2.3 to
				  Solaris-2.5.1

	pattern matcher		- for a convenient user interface
				  (see manual page for more details).
				  To archive/extract a subset of files.

	sophisticated diff	- user tailorable interface for comparing
				  tar archives against file trees
				  This is one of the most interesting parts
				  of the star implementation.

	no namelen limitation	- Pathnames up to 1024 Bytes may be archived.
				  (The same limitation applies to linknames)
				  This limit may be expanded in future
				  without changing the method to record
				  long names.

	deals with all 3 times	- stores/restores all 3 times of a file
				  (even creation time)
				  With POSIX.1-2001 the times are in nanosecond
				  granularity.
				  Star may reset access time after doing
				  backup. On Solaris this can be done without
				  changing the ctime.

	does not clobber files	- more recent copies on disk will not be 
				  clobbered from tape
				  This may be the main advantage over other
				  tar implementations. This allows
				  automatically repairing of corruptions
				  after a crash & fsck (Check for differences
				  after doing this with the diff option).

	automatic byte swap	- star automatically detects swapped archives
				  and transparently reads them the right way

	automatic format detect	- star automatically detects several common
				  archive formats and adopts to them.
				  Supported archive types are:
				  Old tar, gnu tar, ansi tar, star,
				  POSIX.1-2001 PAX, Sun's Solaris tar.


	automatic compression detect - star automatically detects whether the
				  archive is compressed. If it has been
				  compressed with a compression program that
				  is compatible to decompression with "gzip"
				  or "bzip2", star automatically activates
				  decompression.

	fully ansi compatible	- Star is fully ANSI/Posix 1003.1 compatible.
				  See README.otherbugs for a complete
				  description of bugs found in other tar
				  implementations. Star is the first tar
				  implementation that supports POSIX.1-2001.

	support for ACLs and file flags - star supports Access Control Lists
				  and extended file flags (as found on FreeBSD
				  and Linux). Support to archive and restore
				  other file properties may be easily added.

	support for all inode metadata - star supports to put all inode
				  metadata on the archive. This allows future
				  versions of star to perform true
				  incremental dumps.

Have a look at the manual page, it is included in the distribution.

Author:

Joerg Schilling
Seestr. 110
D-13353 Berlin
Germany

Email: 	joerg@schily.isdn.cs.tu-berlin.de, js@cs.tu-berlin.de
	schilling@fokus.fhg.de

Please mail bugs and suggestions to me.