lrzip/WHATS-NEW

lrzip-0.50

Rewrote the file format to be up to 5% more compact and slightly faster.
Made the memory initialisation much more robust, with attempted fallback
to still work even when initial settings fail.
Fixed a lot of the stdin/stdout code.
The two most common scenarios now work without temporary files:
Compression from stdin and decompression to stdout.
Testing of archive integrity no longer writes any temporary files.
Lots more meaningful warnings if failure occurs.
Lots of code cleanups and tidying.

lrzip-0.46

Added lrzuntar which works the same as lrztar -d.

Con Kolivas
May 2010

lrzip-0.45

Added docs for lrztar and lrunzip.
Added distclean and maintainer-clean make targets.
Created git repo: http://github.com/ckolivas/lrzip

Con Kolivas
March 2010

lrzip-0.44

Added an lrztar wrapper to compress / decompress whole directories (finally).
Added -i option to give information about a compressed file.

lrzip-0.43

Darwin support updated. Should build on OSX v10.5+
Finally, stdin/stdout support.
Test archive integrity support.
ZPAQ support in config files.

lrzip-0.42

ZPAQ compression update now shows which rzip stream it's currently compressing
making the update more useful. It also doesn't update unnecessarily with every
byte compressed which was slowing it down a LOT.

lrzip-0.41

ZPAQ compression backend! ZPAQ is from the family of "paq" compressors that
have some of the best compression ratios around, but at the cost of extremely
long compression and equally long decompression times. This can be enabled
with the -z option and makes lrzip archives made with this not backwardly
compatible.

lrzip-0.40

Compression windows should be limited by available ram now on 64bit. The limit
on 32bit is still 2GB.
The compression advantages on large files on 64bit machines with large ram
should be substantially better.
The file format is no longer compatible with earlier versions of lrzip.
Support for decompressing older formats is present, but all new files will
be generated in the new format.
Minor speedups.
Decompression should no longer stall at 4GB boundaries for extended periods
making decompression much faster on files >4GB in size.
Documentation and benchmark updates galore.

lrzip-0.31

The window size limit is now 2GB on both 32bit and 64bit. While it appears to be
smaller than the old windows, only 900MB was being used on .30 even though it
claimed to use more. This can cause huge improvements in the compression of very
large files. Flushing of data to disk between compression windows was
implemented to minimise disk thrashing of read vs write.

Con Kolivas
November 2009

lrzip-0.30

-P option to not set permissions on output files allowing you to write to
braindead filesystems (eg fat32).
Probably other weird and wonderful bugs have been introduced.

Con Kolivas
November 2009

lrzip-0.24 has updated functionality

FEATURE ENHANCEMENTS
lrzip.conf file may be used to set default parameters.
Omit conf using environment: LRZIP=NOCONFIG lrzip.....
LRZIP environment variable may be used in the future
to store certain types of parameters.

LZMA SDK has been upgraded to version 4.63. This
version fixes some problems certain users observed,
and is much simpler using a C-only wrapper
interface.

lrzip now is able to compute an ETA for completion.
In order to do this, the file must be larger than
one compression window in size. That is, is the
compression window is 500MB, and the file is 1GB,
then after the first pass, an ETA will be computed.
If the file is smaller, then no estimate can be made.

lrzip is now able to compute MB/s transfer speeds
for both compression and decompression.

CLEANUPS
Some file cleanups have been done.

Peter Hyman
January 2009
pete@peterhyman.com

lrzip-0.22 update
FEATURE ENHANCEMENTS

-g option. Now supports gzip compression. Very fast!
Expanded dictionary buffer size in lzma compressor.
Variable, expanded dictionary size buffer in both lzma
 compressor and decompressor.
Improved output during compression when using -vv.
Multi-threading supprt when using multiple processors
 or dual core processors when using lzma compression.
 This results in a nearly 2x speed improvement.
Assembler module support to speed up CRC checking.
Improvements in autotools usage, system detection
 and Makefile enhancements.
Lrzip now has a timer that will print total time
 at the end of a compression or decompression if
 -q command line option is not used.

BUG FIX!!!

Even though lrzip uses a compression threshold to
prevent the lzma compressor from getting data that
may not be compressible, there was still a possibility
that lrzip could hang. This was because a data chunk
could contain an uncompressible segment and if the
lzma compressor got it, it would hang.

THANKS TO LASSE COLLIN for uncovering the error in
the lzma wrapper code that was causing the hangup.

January 2008
Peter Hyman
pete@peterhyman.com