davidsen@crdos1.crd.ge.COM (Wm E Davidsen Jr) (06/06/91)
This is the first set of results from data compression tests using the
"new zoo" compressor. Currently the archiver is in alpha test, with a
significant speedup coming in about a month, and production quality
scheduled for August.
The reason for this posting is "proof of existance" for the speed and
performance of the new version, not "look, it's better than X." It
currently is operational on sysv unix, and hopefully will be functional
on BSD, etc, in the next few days. In these tests it seems to provide
slightly better compression and speed than the non-shareware info-zip
version. Since zoo is in alpha and zip is in beta code is available to
testers only, and this is purely a "work in progress" report, to assure
the cbip readers that better compression is on the way.
Rahul has asked me to note that the new compression method is derived
from the Japanese compression program AR002.
I repeat, these are test versions, production source code is not
available yet, please don't waste your time and mine asking.
________________________________________________________________
Results of quick testing of zoo v2.10 alpha. This is an alpha release,
these are alpha test results...
size1 - total of the compressed sizes, reported with v option
size2 - actual file size
o_size - original total size of all files (shown only when changed)
zoo201 - zoo 2.01
zoo210a - zoo 2.10 alpha
zip082 - info-zip 0.82 beta
prog u-cpu s-cpu size1 size2 o_size cmnt
zoo201 3.76 0.26 50272 50938 109204 C sources
zoo210a 10.50 0.34 36155 36821
zip082 14.78 0.78 37400 38160
(w/ -i) 11.96 0.72 37400 38160
zoo201 3.76 0.40 55792 58304 76109 C object (xenix 386)
zoo210a 7.86 0.48 46128 48640
zip082 16.90 1.74 50181 53339
(w/ -i) 13.44 1.30 50211 53369
zoo201 66.48 5.42 916714 929166 1522329 info-zip digests for 1991
zoo210a 142.62 4.96 654674 667126
zip082 239.62 17.24 689379 705409
(w/ -i) 188.92 13.84 689379 705409
zoo x 21.82 7.08 zoo extract
unzip 38.84 5.78 zip extract
Notes on testing: all files were checked with BRIK 32 bit CRC before
compression and after extraction to insure that the extracted versions
were the same as the originals.
--
bill davidsen (davidsen@crdos1.crd.GE.COM -or- uunet!crdgw1!crdos1!davidsen)
"Most of the VAX instructions are in microcode,
but halt and no-op are in hardware for efficiency"