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InstallAware for Windows Installer
 

Compress Better

InstallAware utilizes a very advanced form of LZMA compression, featuring Binary Call Jump converter algorithms that pre-process data to increase compressability before being fed to the actual LZMA algorithm. While LZMA with BCJ2 is optimized especially for program files and crunches data like no other algorithm available today, keep the following points in mind to obtain maximum compression:

  • Files that have been compressed before cannot be recompressed. For example, lets say the size of your uncompressed setup is 36 MB. Assume that when ZIPped, the setup size decreases to 11 MB, and when LZMAd instead, the setup size decreases to 4 MB. Now this might lead us to think that if we use LZMA on the 11 MB ZIP, we would gain an additional 7 MB. This is not the case. No matter how strong a compression algorithm is, it can never recompress files that have been already compressed.
  • Make sure your help files are not pre-compressed. Help compilers may produce compressed output.
  • Make sure your application executables are not pre-compressed. Software protection tools, alongside executable packers, may produce compressed output.
  • Make sure any other data files used by your application are not pre-compressed. For instance, do not compress database files used by your application.
  • If your setup includes MSM (merge module), MSI (installation databases), or EXE (stand-alone setup) files, chances are those files already contain compressed data streams inside them. Use the Setup Decompressor tool to decompress those compressed data streams before including the databases in your setup.
  • If some of your files must be compressed, use maximum compression on them. Remember, pre-compressed files - no matter how weakly they are originally compressed - can never be recompressed.
  • Encrypted files cannot be recompressed.

 Notes

  • Take a look at Microsoft's own application runtime installer sizes, and how much smaller they are when packaged with InstallAware.
  • Rest assured results with your own setups will also be equally remarkable.