Smallest possible file compression size?

[Zach808]

I'm looking for a way to compress the Xcode 4 installer to the smallest possible size (since the App Store insists you keep the stupid installer, or else it's not considered "installed".) This installer takes up 4 and a half gigs of space, and I'm starting to run low. I don't care how fast it compresses/extracts, or whether the compression app is GUI or Command Line driven. I just need the smallest possible file size. I've tried the Archive Utility zip format, tar.gz compression, and p7zip, but they don't seem to compress it more than .03 GB. Is it possible to force programs like Tar to compress into smaller files, or is there another format that compresses better?

 

[Nikh]

Tar doesn't compress, it just packs all data into one file. Try to use 7Zip, it is free and has great compression ratio (if you will use 7z compression algorithm, not zlib).

 

[maflynn]

I use 7zip at work and find that product has the highest compression ratio and generally much faster then winzip (on windows). I'd go with 7zip if you're looking to squeeze every byte as possible.

 

[old-wiz]

Compression depends heavily on what is in the file to be compressed. Executable files tend not to be compressed very much.

 

[peterski]

If you compress the Xcode installer file the Mac App Store will not see it anymore and will show you the Install button all over again. My suggestion would be to delete the installer file. Keep your eyes open for an update, because chances are you'll have to download the 4GB file all over again before apple implements "delta" updates for the Mac App Store into a new version.

 

[al2o3cr]

I've tried the Archive Utility zip format, tar.gz compression, and p7zip, but they don't seem to compress it more than .03 GB. Is it possible to force programs like Tar to compress into smaller files, or is there another format that compresses better?

Not likely - in addition to the issue mentioned by peterski, there's also the fact that 99% of installers are already heavily compressed and thus won't shrink (and may even get bigger) if compressed again. For instance, standard .pkg-format files are actually Xar files:

http://en.wikipedia.org/wiki/Xar_(archiver)

 

[blueroom]

Burn it to a blank DVD.