Tag Archives: 7-Zip

Mr. ZIP promoted the use of ZIP codes for the ...

Mr. ZIP promoted the use of ZIP codes for the USPS during the 1960s and 1970s. (Photo credit: Wikipedia)

Just a quick post about something I just found out: using 7-zip (open source, hence preferred) can be slow. WinRAR has the name to be faster, and co-workers sometimes ask why it is not used instead.

But 7-zip uses multiple compression algorithms. Most of the time, the default algorithm (LZMA) is used. But the option to use the improved LZMA2 has been around for a while. This algorithm has been designed so that it can use multiple cores, whereas LZMA can only use 2 CPU cores effectively. And I have to say: speed increase on “Normal” compression is already 50%. I have not yet checked out the resulting size, but I need a deflation to about 10% of the original file, and that really seems feasible right now (halfway the process).

Maybe you’ve wondered about this, and maybe you already knew this. But if you didn’t yet, I hope I just made your waiting times a bit shorter 🙂

Update: to use the LZMA2-algorithm from the commandline, use the following:

7z a -m0=lzma2 -mmt6 o:\1.7z o:\1.dmp