Hi all,
I have run an extensive series of tests of the JT9 and JT65 decoders in
six different versions of WSJT-X.
Each test involved reading and decoding an identical set of 10,682 *.wav
files. The files were recorded on various bands from 160 m to 10 m. In
these files the number of decodable JT65 signals is typically about 6
times the number of JT9 signals.
Each of the programs was set to "JT9+JT65" mode, and "Deepest" was
selected on the *Decode* menu. Other setup parameters were identical in
all cases. The test computer runs Windows 7 and has an Intel i5-2500
processor with 4 CPUs.
Test results are summarized in the following table. Columns labeled
"JT9" and "JT65" give the number of decoded signals in each mode, from
the full set of 10,682 files.
Program Version JT9 Factor JT65 Factor Time Factor
----------------------------------------------------------
v1.3 r3673 7691 1.000 40831 1.000 14061 1.00
v1.4.0-rc2 r4400 7693 1.000 41796 1.024 13320 1.06
v1.5.0 r4926 7632 0.992 43164 1.057 6644 2.12
v1.5.0 r4950 7632 0.992 43166 1.057 5454 2.58
v1.5.0 r4955 7594 0.987 43948 1.076 4911 2.86
v1.5.0 r4955 OMP 7594 0.987 43946 1.076 4090 3.43
In these tests the decoder in v1.5.0 r4955 is nearly 3 times faster than
the ones in program releases v1.3 r3673 and v1.4.0-rc2 r4400. The last
line in the table used the "OpenMP" version of jt9, and shows that
on modern multi-CPU machines the speed advantage is even greater. The
set of 10.682 files took 3.9 hours to decode with v1.3 r3673, 3.7 hours
with v1.4.0-rc2 r4400, and 1.1 hours with v1.5.0 r4955 OMP.
As well as being much faster, the new decoder produces 7.6% more decoded
signals in JT65 mode. In JT9 mode the number of decodes is very
slightly (1.3%) smaller. This result is a consequence of my having so
far concentrated mostly on speed improvements. I think it may be
possible now improve the number of decodes, while keeping the speed
improvements already achieved. I will turn my attention to that problem
soon.
-- 73, Joe, K1JT
------------------------------------------------------------------------------
Dive into the World of Parallel Programming. The Go Parallel Website,
sponsored by Intel and developed in partnership with Slashdot Media, is your
hub for all things parallel software development, from weekly thought
leadership blogs to news, videos, case studies, tutorials and more. Take a
look and join the conversation now. http://goparallel.sourceforge.net/
_______________________________________________
wsjt-devel mailing list
wsjt-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/wsjt-devel
