Download WinRAR 4.20 Beta 1

RAR Labs has released the first beta release of version 4.20 of its RAR and WinRAR archiving tools. The popular compression tool is available for a variety of operating systems, including Windows, Linux, and Mac OS X. The program handles most common formats – including rar, zip, cab, arj, lzh, tar, gz, ace, uue, bz2, jar , iso, 7z and z – has a skinnable interface and support for Zip64 and multivolume cab files. In version 4.20, changes have been made to the compression algorithm, among other things. This makes it generally faster, but the memory usage has increased considerably. In addition, it is now also possible to search in 7-zip archive files and support for Windows 2000 has been dropped. The full changelog looks like this:

New in version 4.20 beta 1

• Changes to the RAR compression:
  • The general data RAR compression algorithm is optimized for better utilization of multiple processor cores. While even speed gains are possible with a single processor, best results will be achieved in a multi-core environment. The speed gain depends on the type of data and the average file size. Multiple cores are used more efficiently when compressing large files. We measured a doubling of speed on a mixed group of files, consisting of large text files and executable files, and even a tripling of compression speed on data with low redundancy, such as JPG and MP3 files, compared to version 4.11 on a CPU with 4 cores and 8 threads;
  • We had to increase the memory requirements to achieve the higher compression rate. The new version occupies about 120 MB for the compression data structures, while it was 40 MB in WinRAR 4.11;
  • The RAR text data compression algorithm cannot efficiently utilize multiple CPU cores, resulting in much lower performance in a multi-processor environment as compared to the general data algorithm. Also, the extraction speed is much lower than in the general algorithm, regardless of the number of CPUs. This is why we decided to disable the text algorithm by default. If you want the maximum compression ratio for text data independent of speed, you can enable text compression in the “Extended compression parameters” dialog box. Press the “Compression…” button on the “Extended” page of the packing dialog to access it. You can also permanently change this option to the default compression profile; In command line mode, text compression can be enabled with the ‘-mct’ switch.
  • The ‘Fastest’ (‘-m1’) compression mode now also supports multiple processor cores. In 4.10 only a single processor core was used.
• The general data RAR decompression algorithm is also faster, but not equivalent to the RAR compression. A speed increase of 10 to 15% is possible, compared to version 4.11. RAR decompression is not capable of using multiple processor cores, so speed gains are not dependent on the number of cores.
• Changes to the ZIP compression:
  • ZIP compression now supports multiple processor cores for vastly improved performance, up to 3 times faster on a 4-core, 8-threaded CPU. Single CPU performance has also been improved;
  • the memory usage for ZIP compression has been increased to approximately 15 MB.
• Creating and processing recovery volumes can now use multiple CPU cores, resulting in faster speed. Despite that, in most situations, hard drive search speed will be the limiting factor for recovery volumes. This means that the speed gains are best noticed when using solid state drives (SSD).
• The allowed ‘ ‘ value for the ‘-mt ‘ switch is now 1 – 32, not 0 – 16 as in previous versions.
• The ‘Find Files’ command will now search 7-Zip archives. Previously, the .7z archive format was not supported by ‘Find Files’
• Windows 2000 is no longer supported by WinRAR and WinRAR’s self-extracting modules.

The following downloads are available:
WinRAR 4.20 beta 1 (32bit)
WinRAR 4.20 beta 1 (64bit)
RAR 4.20 beta 1 for Linux (32bit)
RAR 4.20 beta 1 for Linux (64bit)
RAR 4.20 beta 1 for FreeBSD
RAR 4.20 beta 1 for Mac OS X