From: djtooley@undergrad.math.waterloo.edu (Doug Tooley)
Subject: PKZIP 2.04c vs. ARJ 2.39b (and LHA/ZOO) Compression Results ** UPDATED
Followup-To: comp.compression
Summary:  PKZIP is fast, but unreliable. I'm going with ARJ
Keywords: archive compress ARJ PKZIP LHA ZOO
Organization: University of Waterloo
Date: Sat, 9 Jan 1993 05:30:07 GMT

*** (Updated to include ARJ v2.39b - Please see notes) ***
 
Results of Compression Testing: PKZIP v2.04c.          Jan 08/92
 
Data:       Contents of ARJ230.EXE and PKZ204C.EXE
		      (with duplicate filenames renamed/included)
Total Size: 720937 bytes
Archivers:  PKZIP204c PKZIP110 PKZIP193a ARJ230 ARJ239b LHA213 ZOO210
Machine:    386/33, 10M RAM  \w 128k BIOS Shadow RAM   (\w QEMM)
Drive:      Seagate ST296N (84M)  SCSI controller   (no s/w cache)
Timing:     Norton Utilities'  TM.EXE  v4.50
Execution:  MSDOS BATch file
 
Results:
 
 TIME    FILENAME        SIZE      COMMAND
 
Sorted by Size
 
27 secs  ZIP204X  ZIP    358090    pkzip -ex
35 secs  ARJ239JM ARJ    359598    arj a -jm
55 secs  ARJ230JM ARJ    359725    arj a -jm
33 secs  ARJ239   ARJ    359734    arj a   
36 secs  ARJ239M1 ARJ    359736    arj a -m1
23 secs  ZIP204   ZIP    360153    pkzip
21 secs  ZIP204N  ZIP    360153    pkzip -en
47 secs  ARJ230   ARJ    360228    arj a
48 secs  ARJ230M1 ARJ    360230    arj a -m1
32 secs  ARJ239M2 ARJ    361577    arj a -m2
22 secs  ZIP193   ZIP    362995    pkzip
44 secs  ARJ230M2 ARJ    363519    arj a -m2
48 secs  LHA213   LZH    368780    lha a
19 secs  ZIP204F  ZIP    369940    pkzip -ef
94 secs  ZOO210H  ZOO    370481    zoo ah
29 secs  ARJ239M3 ARJ    370557    arj a -m3
35 secs  ARJ230M3 ARJ    371169    arj a -m3
26 secs  ZIP110   ZIP    381182    pkzip
15 secs  ZIP204S  ZIP    393321    pkzip -es
27 secs  ARJ239M4 ARJ    400019    arj a -m4
69 secs  ZOO210   ZOO    459204    zoo a
24 secs  ARJ230M0 ARJ    723239    arj a -m0
18 secs  ARJ239M0 ARJ    723239    arj a -m0
14 secs  ZIP2040  ZIP    724559    pkzip -e0
 
Sorted by Time
 
14 secs  ZIP2040  ZIP    724559    pkzip -e0
15 secs  ZIP204S  ZIP    393321    pkzip -es
18 secs  ARJ239M0 ARJ    723239    arj a -m0
19 secs  ZIP204F  ZIP    369940    pkzip -ef
21 secs  ZIP204N  ZIP    360153    pkzip -en
22 secs  ZIP193   ZIP    362995    pkzip
23 secs  ZIP204   ZIP    360153    pkzip
24 secs  ARJ230M0 ARJ    723239    arj a -m0
26 secs  ZIP110   ZIP    381182    pkzip
27 secs  ARJ239M4 ARJ    400019    arj a -m4
27 secs  ZIP204X  ZIP    358090    pkzip -ex
29 secs  ARJ239M3 ARJ    370557    arj a -m3
32 secs  ARJ239M2 ARJ    361577    arj a -m2
33 secs  ARJ239   ARJ    359734    arj a   
35 secs  ARJ230M3 ARJ    371169    arj a -m3
35 secs  ARJ239JM ARJ    359598    arj a -jm
36 secs  ARJ239M1 ARJ    359736    arj a -m1
44 secs  ARJ230M2 ARJ    363519    arj a -m2
47 secs  ARJ230   ARJ    360228    arj a
48 secs  ARJ230M1 ARJ    360230    arj a -m1
48 secs  LHA213   LZH    368780    lha a
55 secs  ARJ230JM ARJ    359725    arj a -jm
69 secs  ZOO210   ZOO    459204    zoo a
94 secs  ZOO210H  ZOO    370481    zoo ah
 
Sorted by Name  (for the scroll-back impaired)
 
47 secs  ARJ230   ARJ    360228    arj a
55 secs  ARJ230JM ARJ    359725    arj a -jm
24 secs  ARJ230M0 ARJ    723239    arj a -m0
48 secs  ARJ230M1 ARJ    360230    arj a -m1
44 secs  ARJ230M2 ARJ    363519    arj a -m2
35 secs  ARJ230M3 ARJ    371169    arj a -m3
33 secs  ARJ239   ARJ    359734    arj a   
35 secs  ARJ239JM ARJ    359598    arj a -jm
18 secs  ARJ239M0 ARJ    723239    arj a -m0
36 secs  ARJ239M1 ARJ    359736    arj a -m1
32 secs  ARJ239M2 ARJ    361577    arj a -m2
29 secs  ARJ239M3 ARJ    370557    arj a -m3
27 secs  ARJ239M4 ARJ    400019    arj a -m4
48 secs  LHA213   LZH    368780    lha a
26 secs  ZIP110   ZIP    381182    pkzip
22 secs  ZIP193   ZIP    362995    pkzip
23 secs  ZIP204   ZIP    360153    pkzip
14 secs  ZIP2040  ZIP    724559    pkzip -e0
19 secs  ZIP204F  ZIP    369940    pkzip -ef
21 secs  ZIP204N  ZIP    360153    pkzip -en
15 secs  ZIP204S  ZIP    393321    pkzip -es
27 secs  ZIP204X  ZIP    358090    pkzip -ex
69 secs  ZOO210   ZOO    459204    zoo a
94 secs  ZOO210H  ZOO    370481    zoo ah
 
 
My comments:
 
** WARNING **
 PKZIP 2.04c is apparently far from bug free. Some of these include:
 The possibility of data-loss, especially wrt multiple volumes.
 Problems with volume label storage, and their "more advanced PC" handing
 is reported to have errors. Also, CRC checking has been failing
 in some cases where it shouldn't have. "From what I have read on the net."
 
I congratulate PKWARE on the speed and compression of their program, but
the best way to damage consumer confidence is to release a long-awaited
product and have it "full of bugs".  It leads one to ask: "Testing?!?"
 
I also congratulate Robert K. Jung on his Beta version of ARJ. I was 
quite impressed by the improved speed (especially at the maximum (-jm)
compression level, which is what I use normally.)  I much prefer ARJ's
handing of volume splitting over that of the new PKZIP.  ARJ has proven
itself to have the options, ease of use, reliability and now
speed for me to use it as my #1 compression/archiving program.
(I sound like a commercial. :)
 
My previous comments heralded PKZIP as #1, but with their bug reports
and ARJ's improved speed I have decided to wait the extra 7 seconds
for a more little reliability.  I'm going to continue to use ARJ.
 
	--- Doug
 
...."I haven't lost my mind, I know exactly where I left it."................
Doug Tooley             3B Co-Op CS student at U of Waterloo, Ontario, Canada
djtooley@{descartes|napier|cayley}.uwaterloo.ca            
Newsgroups: comp.compression