I want to reinstall my OS, but I don't have the hard drive space to backup any more (I have a RAID 1 array, so I haven't done it for a while). In my /home I have 284.8 GiB of data, and I have a spare 250 GB (or 217.4 GiB) hard drive that I've been using for backup.
What type of compression algorithm (if any) is capable of this type of compression? I don't care about the time, I have a quad core though, so something that utilizes all 4 cores would be great.
I have tried 7zip with no success. Ran on one core for two days and failed because of lack of space.