The small files option compressed the HTML version of War and Peace (3.64 MB) to 725 KB, which is 22.4% smaller than the 934 KB with the default options. No other combination of options tried improved upon this. With the above large file options it compressed to 1210 KB, or 26.3% smaller.
With the default o ptions (just “7z a”), a 916 MB test log file compressed from 916 MB to 1656 KB. If you need compatibility with other tools, here is the maximum ZIP file compression (note mpass can be made as large as you want, but rapidly becomes very slow):ħz a -tzip -mx=9 -mfb=258 -mpass=20 archive.zip Warning: Compression will be very slow, and files created using these options may require a lot of memory to decompress.
