Versions tested:0.60, 0.666
Optimal parameters:-mex4
Links:http://freearc.org
Authors:Bulat Ziganshin, Dmitry Shkarin, Ilya Grebnov, Igor Pavlov
Algorithms:LZ+HUF, LZ+ARI, PPMII, BWT/ST+WFC/MTF, X86, LZP, DICT
Notable peformances:Application1, Application3, Application4, Database1, Game1, Game2, Image1, OS1, PGN1, Pitches1, Text1, Text2

freearc

FreeArc is an open source project maintained by Bulat Ziganshin. It combines his original work: tornado, Rep, Dict, delta preprocessing, improvements for LZMA match finding and much more. It also integrates open source compressors ppmd, LZMA (7-zip), grzipii and tta.

On February 22, 2009 the author submitted following switches: '-m1', '-m2', '-m3', '-mx', '-m9x'. Because the unarc/sfx codebase v0.50a requires multiple times of the needed memory, the author suggested '-m6' to be tested instead of '-mx'.

On April 18, 2010 updated configurations were submitted: -mex1..-mex5.

To avoid an error 'can't allocate memory required for (de)compression in...' in 0.60 for some modes -lc should be used to l limit memory usage: "-lc actually limits working set rather than puts hard limit on virtual memory usage"email

0.666 submitted on May 20, 2010 with following configurations: "-m1, -m2, -m3, -m4, -mx -lc500m, -m9d -lc500m".

other options (-mex..) should become obsolete - now FreeArc automatically uses as much cores as available. also i've fixed part of problems in memory handling you've found and -lc500m should use only 550-600 mb of memory.
email May 20, 2010

(Have info that should be added here? E-mail.)


We use arc.exe+arc.groups for compressing.

Qualified configurations
VerRatingCPRDPRS.E.R.E.RatioC. kB/sD. kB/s
<none>
0.60877103031920543044.502434815939
-m1 (-mex1)
0.6047101634412.8075750043827
0.6069+47%+51%++54%+2.790-0.6%94008+63%67124+53%
0.66666-4.3%-2.0%--3.2%2.7900%92158-2.0%64394-4.1%
-m2 (-mex2)
0.60378525883822313.5821783435360
0.60612+62%+112%+9.1%+85%+33%3.516-1.8%45753+157%46962+33%
0.666641+4.7%+7.3%+2.1%-3.7%+18%3.557+1.2%43606-4.7%42570-9.4%
-m3 (-mex3)
0.6074690524227019614.180712722633
0.601406+88%+148%+7.0%+152%+25%3.992-4.5%26665+274%36576+62%
0.6661333-5.2%-6.6%-3.1%-5.9%-4.3%3.996+0.1%24683-7.4%35018-4.3%
-m4 (-mex4)
0.601599196050346557534.3361127734267
0.6661443-9.8%-12%-1.0%-9.5%-10%4.334-0%9926-12%34102-0.5%
-m9d -lc500m (-m9x -lc350)
0.6054855250513724504.451255927703
0.666726+32%+33%+25%+11%+70%4.588+3.1%2663+4.1%27049-2.4%
-mex5
0.601065128934827445654.428622319916
-mx -lc500m (-m6 -lc350)
0.6077885737215548054.633287514798
0.666787+1.2%+0.9%+3.0%-3.2%+7.3%4.668+0.8%2734-4.9%14330-3.2%

Version info

0.60, tar: no, mode: 32-bit, crc32: 44387fdc, decoder: 72 kB
compression: arc.exe a -r <args> <cfile> <src>
decompression: arc.exe x <cfile>
0.666, tar: no, mode: 32-bit, crc32: 4655019d, decoder: 74 kB
compression: arc.exe a -r <args> <cfile> <src>
decompression: arc.exe x <cfile>