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Re^7: Firefly Bug

alex
yakovenko.alexander@gmail.com

Thank you a lot for so detailed letter.
> First, I did not completely understand whether you are running Firefly in parallel mode, or in serial just using several working threads specified via mklnp or np variable in the $contrl group, or both?
Sorry for poor details. I tried all combination: serial run, 2 serial runs, parallel and 2 parallel runs. All of them are corrupted.
About Hyper Threading. Our cluster has HT ‘off’ so HT ‘on’ was tried on my personal workstation only. Moreover the amount of cores grows but nodes are still equipped with 1 HDD to save on setup and maintaining … so I can use only ‘direct’ methods and even so 2 MP2 energy runs on 8-cores node with 1 hdd  brings it down so I can hardly ssh there.  For this reason HT it is not interesting for me (and if you interested in my stupid opinion it is good for you to gain performance in direct methods which are better adapted to SMP era). Particularly I tried HT just to check if probability of dead-lock depends on it (seems it is not).
> Second, what is the exact version (the exact filename of the Firefly's distribution archive) you are using? The point is that the fully statically linked MPICH version uses old threading model (i.e., it does not use pthreads) and indeed internally it uses sysvipc semaphores. All other versions uses pthreads threading model and do not use semaphores at all - however, MPICH itself (that is configured to use ch_p4 device) uses them. Thus, even semi-statically linked MPICH version indirectly uses semaphores. Versions for all other MPI implementations may or may not indirectly use semaphores depending on the details of the particular implementation of MPI.
Currently I work with firefly 71G. I have experienced the problem in all cases: full static firefly, serial run;  MPICH2 firefly, serial run;  MPICH2 firefly, parallel run. Haven’t checked anything else, sorry. The only reason I suggested problems with semaphores is my own experience in parallel development, forget about it if you using something else.
P.S. fill free to ask about any details that would help you to make firefly better.
Alex.


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