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, Application4, Game1, Game2, OS1, Pitches1

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
Ver Rating CPR DPR S.E. R.E. Ratio C. kB/s D. kB/s
<none>
0.60 882 1035 320 207 435 4.502 4348 15939
-m1 (-mex1)
0.60 47 100 6 344 0 2.807 57500 43827
0.60 68 +45% +51% + +54% 2.790 -0.6% 94008 +63% 67124 +53%
0.666 66 -2.9% -2.0% - -3.2% 2.790 0% 92158 -2.0% 64394 -4.1%
-m2 (-mex2)
0.60 378 524 87 383 23 3.582 17834 35360
0.60 611 +62% +112% +10% +85% +30% 3.516 -1.8% 45753 +157% 46962 +33%
0.666 639 +4.6% +7.4% +2.1% -3.7% +20% 3.557 +1.2% 43606 -4.7% 42570 -9.4%
-m3 (-mex3)
0.60 748 908 243 272 197 4.180 7127 22633
0.60 1409 +88% +147% +7.0% +151% +24% 3.992 -4.5% 26665 +274% 36576 +62%
0.666 1335 -5.3% -6.5% -3.5% -5.8% -4.1% 3.996 +0.1% 24683 -7.4% 35018 -4.3%
-m4 (-mex4)
0.60 1606 1968 505 468 580 4.336 11277 34267
0.666 1449 -9.8% -12% -1.0% -9.6% -10% 4.334 -0% 9926 -12% 34102 -0.5%
-m9d -lc500m (-m9x -lc350)
0.60 551 555 508 138 247 4.451 2559 27703
0.666 730 +32% +33% +25% +11% +70% 4.588 +3.1% 2663 +4.1% 27049 -2.4%
-mex5
0.60 1070 1295 350 275 460 4.428 6223 19916
-mx -lc500m (-m6 -lc350)
0.60 783 862 375 156 486 4.633 2875 14798
0.666 792 +1.1% +0.9% +2.7% -3.2% +7.4% 4.668 +0.8% 2734 -4.9% 14330 -3.2%

Version info

0.60, tar: no, mode: 32-bit, crc32: 44387fdc, decoder: 72 kB, tested: 2010 Apr 16
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, tested: 2010 May 20
compression: arc.exe a -r <args> <cfile> <src>
decompression: arc.exe x <cfile>