- Update to version 21.06
* Bug in LZMA encoder in file LzmaEnc.c was fixed:
LzmaEnc_MemEncode(), LzmaEncode() and LzmaCompress() could
work incorrectly, if size value for output buffer is smaller
than size required for all compressed data. LzmaEnc_Encode()
could work incorrectly, if callback ISeqOutStream::Write()
doesn't write all compressed data.
NCompress::NLzma::CEncoder::Code() could work incorrectly,
if callback ISequentialOutStream::Write() returns error
code.
* Bug in versions 21.00-21.05 was fixed:
7-Zip didn't set attributes of directories during archive
extracting.
version 21.04 beta:
* 7-Zip now reduces the number of working CPU threads for
compression, if RAM size is not enough for compression with
big LZMA2 dictionary.
* 7-Zip now can create and check "file.sha256" text files that
contain the list of file names and SHA-256 checksums in
format compatible with sha256sum program.
version 21.03 beta:
* The maximum dictionary size for LZMA/LZMA2 compressing was
increased to 4 GB (3840 MiB).
* Minor speed optimizations in LZMA/LZMA2 compressing.
version 21.02 alpha:
* The speed for LZMA and LZMA2 decompression in arm64 versions
was increased by 20%-60%.
version 21.01 alpha:
* The improvements for speed of ARM64 version using hardware
CPU instructions for AES, CRC-32, SHA-1 and SHA-256.
* Some bugs were fixed.
version 20.02 alpha:
* The default number of LZMA2 chunks per solid block in 7z
archive was increased to 64. It allows to increase the
compression speed for big 7z archives, if there is a big
number of CPU cores and threads.
* The speed of PPMd compressing/decompressing was increased
for 7z archives.
* The new -ssp switch. If the switch -ssp is specified, 7-Zip
doesn't allow the system to modify "Last Access Time"
property of source files for archiving and hashing operations.
* Some bugs were fixed.
version 20.00 alpha;
* 7-Zip now supports new optional match finders for LZMA/LZMA2
compression: bt5 and hc5, that can work faster than bt4 and
hc4 match finders for the data with big redundancy.
* The compression ratio was improved for Fast and Fastest
compression levels with the following default settings:
+ Fastest level (-mx1) : hc5 match finder with 256 KB
dictionary.
+ Fast level (-mx3) : hc5 match finder with 4 MB
dictionary.
* Minor speed optimizations in multithreaded LZMA/LZMA2
compression for Normal/Maximum/Ultra compression levels.