Hi All, some developers and testers of WSJT-X have been using the optimized jt9_omp program to get parallel decoding of JT65 and JT9, until now a patch was required to use this version.
Now that the OpenMP parallel decoding variant of jt9 has stabilized, is avaiable on all platforms and, seems to be very effective; I have changed the CMake build script to use it by default. The patch is no longer required. There is no jt9_omp program any more. One consequence of parallel decoding is that in dual JT65 and JT9 decodes are interleaved. Also even though the same code as before to decode the Rx frequency quickly is in place, a decode from the "other" mode may win the race and be displayed first. The "on frequency" decode is still being delivered as quickly as is possible. If you want to test without parallel decoding, the OpenMP code can be constrained to use only one thread thus casing sequential decoding of modes in dual mode as before. This is done by defining the environment variable OMP_THREAD_LIMIT=1, doing this could increase the overall decoding elapsed time by up to 100% and will always delay the non-Tx mode decodes. Also introduced in this change is a higher "patience" value for the FFTW3 FTT plans, this means that the very first time a decode is initiated from the jt9 program or WSJT-X a considerable time will elapse while FFTW optimizes the FFT plans for your hardware. This could take several minutes, don't assume WSJT-X is hanging, let it finish otherwise it will have to do it all over again the next time you start WSJT-X. This higher optimization level only gives a small performance improvement but apart from the initial calculations it costs nothing so is probably worth the patience. 73 Bill G4WJS. ------------------------------------------------------------------------------ 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
