WinRAR 4.20 官方簡體中文正式版發布下載，伴隨如下更新和改進：
在WinRAR 4.20 中，RAR和ZIP的壓縮都得到改進，其中RAR的常規壓縮算法優化，更好利用多核心處理器；另外，RAR的解壓算法也有所提升。「查找文件」命令支持7-Zip中的數據，WinRAR和WinRAR自解壓模塊將不再支持Windows2000作業系統。
WinRAR是一款流行好用的壓縮工具，支持滑鼠拖放及外殼擴展，完美支持 ZIP 檔案，內置程序可以解開 CAB、ARJ、LZH、TAR、GZ、ACE、UUE、BZ2、JAR、ISO 等多種類型的壓縮文件；具有估計壓縮功能，你可以在壓縮文件之前得到用 ZIP 和 RAR 兩種壓縮工具各三種壓縮方式下的大概壓縮率；具有歷史記錄和收藏夾功能；壓縮率相當高，而資源佔用相對較少、固定壓縮、多媒體壓縮和多卷自釋放壓縮是大多壓縮工具所不具備的。
WinRAR 4.20 正式版 更新內容：
1. Changes in RAR compression:
a) RAR general compression algorithm is optimized for betterutilization of several processor cores. While some speed gain is possible even in single processor mode, best resultsare achieved in multi-core environment.
Speed gain depends on data type and average file size.Several cores are utilized more efficiently when compressinglarge files.
b) we had to increase memory requirements to achieve higher compression speed. General RAR compression algorithm allocates
about 120 MB comparing to 40 MB in WinRAR 4.11;
c) RAR text compression algorithm cannot utilize several CPU cores efficiently, so its performance in multiprocessor environment is much lower than for general algorithm. Also its decompression speed is much lower than in general algorithm regardless of CPU number. So we decided to disable the text algorithm by default.
If you need maximum possible compression ratio for plain text data regardless of speed, you can enable the text compression in "Advanced compression parameter" dialog. Press "Compression..." button on "Advanced" page of archiving dialog to access it.
You can also change this option permanently in default compression profile;
In the command line mode the text compression can be enabled with -mct switch;
d) "Fastest" (-m1) compression mode also supports several processor cores now. In 4.11 it could use only a single processor core.
2. RAR general decompression algorithm speed is slightly improved,though not to same extent as RAR compression. RAR decompression is not able to use several processor cores, so its performance does not depend on a number of cores.
3. Changes in ZIP compression:
a) now ZIP compression supports several processor cores resulting in noticeably higher performance in multi-core environment. Single CPU ZIP compression is also faster than in 4.11;
b) memory use for ZIP compression is increased to about 15 MB.
4. Recovery volume creating and processing can use several CPU cores resulting in higher speed. Though, typically hard drive seek speed is a limiting factor for recovery volumes, so this gain is most noticeable when working with solid state drive.
5. Now the allowed value for -mt switch is 1 - 32, not 0 - 16 as before.
6. "Find files" command can search data in 7-Zip archives.
Previously "Find files" did not support .7z archive format.
7. Windows 2000 is not supported by WinRAR and WinRAR self-extracting modules anymore.
8. "Save current settings" button in "Advanced SFX options" dialog is now available only when converting an existing archive to SFX.
Options saved with this button are applied only to convert to SFX operation.
If you create or update SFX archive, only SFX options stored in default compression profile are used. Options saved in "Advanced SFX options" dialog are ignored for these operations.
運行環境：Windows XP/Vista/Win7等
WinRAR 4.20 官方簡體中文正式版32位下載：
（1.6MB）
WinRAR 4.20 官方簡體中文正式版64位下載：
（1.7MB）
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