02 August 2009

7-Zip 9 beta has new LZMA2 format

After trying the beta version for about 2 month. I just recently know that it support .xz extension (use LZMA2 compression). Later it revealed that .xz only available when we compress single file that's why I kind of skip that new format.

Interesting enough the LZMA2 didn't have advantage over old LZMA (.7z). In my test regardless the file type (plain-text or binary) LZMA2 result is on par with LZMA infact in some binary (Mplayer.exe file) LZMA beat the new format a bit. Worse, LZMA2 required more than twice memory (a mere 2GB) at the same "maximum" setting.

Maybe this is why 7-zip 9 still in beta. We should wait then...

1 comment:

  1. With at least the 9.15 beta, LZMA2 will use all 6 cores on a hex core CPU, while LZMA will not. On a test from and to a RAMDISK, LZMA "Fastest" got 65MB/s, and LZMA2 "Fastest" got 300MB/s.

    BZip2, as an interesting point, also uses a hex core machine fully, as does basic Zip Deflate and Deflate64.