简介
7-Zip，一款世界流行的免费开源压缩软件。7-Zip一款老牌压缩工具，拥有极高的压缩算法以及免费开源的压缩文件管理器，提供了命令行接口和图形界面操作，支持独立的7z格式以及近乎所有流行的压缩格式，包括ZIP、RAR、ISO、CAB、GZIP、BZIP2、TAR等。其多线程的LZMA压缩要比普通ZIP文件压缩率高达30-50%，还可以把ZIP格式的文件再次压缩2-10%。
更新
History of the 7-Zip
https://www.7-zip.org/history.txt
- 21.07 2021-12-26
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7-Zip now can extract VHDX disk images (Microsoft Hyper-V Virtual Hard Disk v2 format). - New switches: -spm and -im!{file_path} to exclude directories from processing for specified paths that don’t contain path separator character at the end of path.
- In the “Add to Archive” window, now it is allowed to use -m prefix for “Parameters” field as in command line: -mparam.
- The sorting order of files in archives was slightly changed to be more consistentfor cases where the name of some directory is the same as the prefix part of the name of another directory or file.
- TAR archives created by 7-Zip now are more consistent with archives created by GNU TAR program.
7-Zip 21.06 2021-11-24
- The window “Add to Archive” now allows to set a limit on memory usage (RAM) that will be used for compressing.
- New switch -mmemuse={N}g / -mmemuse=p{N} to set a limit on memory usage (RAM) for compressing and decompressing.
- Bug in versions 21.00-21.05 was fixed:7-Zip didn’t set attributes of directories during archive extracting.
- Some bugs were fixed.
提供创建和测试“sha256”文件的右键菜单命令：
7-Zip / CRC SHA / SHA-256 -> file.sha256
7-Zip / CRC SHA / Test Archive : Checksum
命令行版命令：
- 7z a -thash file.sha256 *.txt
- 7z t -thash file.sha256
- 7z t -thash -shd. file.sha256
新的 -shd{dir_path} 开关来设置用于检查文件目录
由“file.sha256”文件引用以进行“测试”操作。
如果未指定 -shd{dir_path}，将使用存储“file.sha256”的目录
最近主要更新：
- 优化了 LZMA/LZMA2压缩算法的速度
- 增加LZMA/LZMA2压缩算法最大字典到4GB (3840MiB)
- LZMA2压缩算法中每个固实块的大小数量已增加到64GB。
- 固实块越大，大型7z压缩文件的压缩速度CPU线程就越高。
- 给7Z/ZIP/RAR压缩文件类型加入了PPMd压缩/解压缩的速度。
其他
极限压缩比参数设置
压缩等级>极限，算法>LZMA2, 字典>256MB, 单词大小->273
固实块大小->固实, CPU线程->6或8, 底部的参数框填入f=BCJ2
