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-- Pavel Banáš pavel.banas.upol.cz Department of Physical Chemistry, Palacky University Olomouc Czech Republic ---------- Původní zpráva ---------- Od: Ross Walker <ross.rosswalker.co.uk> Komu: AMBER Mailing List <amber.ambermd.org> Datum: 3. 3. 2014 22:50:31 Předmět: Re: [AMBER] pmemd.cuda segfaults "Hi Pavel, I guarantee you this is a hardware issue. It is either that they are Titan-Black cards or they are faulty Titan cards. It could also be an overheating issue, that case you showed is not ducted - way to check that is to pull all but one of the GPUs and see if it works. It could be a motherboard issue but I doubt it if the machine is working properly and CPU runs don't randomly crash. FYI this is what you should see in mdout for Titan |------------------- GPU DEVICE INFO -------------------- | | CUDA Capable Devices Detected: 1 | CUDA Device ID in use: 0 | CUDA Device Name: GeForce GTX TITAN | CUDA Device Global Mem Size: 6143 MB | CUDA Device Num Multiprocessors: 14 | CUDA Device Core Freq: 0.88 GHz | |-------------------------------------------------------- and for Titan-Black |------------------- GPU DEVICE INFO -------------------- | | CUDA Capable Devices Detected: 1 | CUDA Device ID in use: 0 | CUDA Device Name: GeForce GTX TITAN Black | CUDA Device Global Mem Size: 6143 MB | CUDA Device Num Multiprocessors: 15 | CUDA Device Core Freq: 0.98 GHz | |-------------------------------------------------------- To test things build AMBER with GCC and CUDA5.0 (we recommend 5.0 since 5.5 and 6.0 are about a 5 to 8% performance regression), download the following: https://dl.dropboxusercontent.com/u/708185/GPU_Validation_Test.tar.gz then export AMBERHOME=/path_to_amber12 tar xvzf GPU_Validation_Test.tar.gz cd GPU_Validation_Test ./run_test_4gpu.x Let it run until it completes - about 5 hours and then let us know what the 4 log files that you get contain. All the best Ross On 3/3/14, 12:44 PM, "pavel.banas.upol.cz" <pavel.banas.upol.cz> wrote: > >Dear all, > >Thanks for all comments and suggestions. In order to simplify things, I >will >put all my answers together. > > > >> Are these 'Titan' cards or Titan-Black cards? > > > >Actually don't know exactly. Nvidia-smi says just 'GeForce GTX TITAN' and >I >can't get anything conclusive from lspci, but assuming the core frequency >mentioned in AMBER output 0.88 GHz, this would speak for TITAN-black. I >will >check it, but not before tomorrow as this is remote machine. > > > >> I think that not many of us are building pmemd.cuda with Intel > > compilers. Compared to using GCC, there is no performance gain to be > > expected. And since Intel compilers are not exactly known for >equivalent > > behavior among different releases, it might very well be that you had > > bad luck in your combination of things. Did you really try CUDA >toolkit > > 5.0 together with older Intel compilers? > > > >No, we just tested older compiler with toolkit 5.5 and older toolkit with >new compiler. If we do not have titans-black cards, we will definitely >check >gcc and after that even the combination of older toolkit and intel >compiler. > > > >> .Pavel: If you know how to use gdb/idb, you can add the "-g" flag to the >> pmemd compiler defined in config.h (to add debugging symbols) and then >> use idb/gdb to get the stack trace of the resulting core dump. That >> should at least tell us where the segfault is occurring. > > > >We indeed compiled the code with "-g" and used gdb, attached you can find >two of error messages. > > > >Anyway, many thanks to all of you. I will definitely check, whether we >have >titans or titan-black cards and if titans, we will try to use gnu >compilers >and let you know. > >Thank you very much, > >Pavel > >-- >Pavel Banáš >pavel.banas.upol.cz >Department of Physical Chemistry, >Palacky University Olomouc >Czech Republic > > > >---------- Původní zpráva ---------- >Od: Ross Walker <ross.rosswalker.co.uk> >Komu: AMBER Mailing List <amber.ambermd.org> >Datum: 3. 3. 2014 18:07:31 >Předmět: Re: [AMBER] pmemd.cuda segfaults > >"Forget the debugging. It is a hardware issue for sure. > >Main thing to know is if these are Titan or Titan-Black. If they are >Titan-Black then all bets are off. Titan-Black are currently not supported >due to the fact the cards give incorrect results. A bug is filed with >NVIDIA. Until it is fixed they will remain unusable. > >All the best >Ross > > > > >On 3/3/14, 9:01 AM, "Jason Swails" <jason.swails.gmail.com> wrote: > >>On Mon, 2014-03-03 at 17:44 +0100, Jan-Philip Gehrcke wrote: >>> Hello Pavel, >>> >>> I think that not many of us are building pmemd.cuda with Intel >>> compilers. >> >>FWIW, I always use this combination on my machine with a GTX 680 and an >>AMD 6-core processor; mainly out of habit. I've never seen any >>problems. >> >>.Pavel: If you know how to use gdb/idb, you can add the "-g" flag to the >>pmemd compiler defined in config.h (to add debugging symbols) and then >>use idb/gdb to get the stack trace of the resulting core dump. That >>should at least tell us where the segfault is occurring. >> >>HTH, >>Jason >> >>-- >>Jason M. Swails >>BioMaPS, >>Rutgers University >>Postdoctoral Researcher >> >> >>_______________________________________________ >>AMBER mailing list >>AMBER.ambermd.org >>http://lists.ambermd.org/mailman/listinfo/amber > > > >_______________________________________________ >AMBER mailing list >AMBER.ambermd.org >http://lists.ambermd.org/mailman/listinfo/amber"=_________________________ >______________________ >AMBER mailing list >AMBER.ambermd.org >http://lists.ambermd.org/mailman/listinfo/amber _______________________________________________ AMBER mailing list AMBER.ambermd.org http://lists.ambermd.org/mailman/listinfo/amber" _______________________________________________ AMBER mailing list AMBER.ambermd.org http://lists.ambermd.org/mailman/listinfo/amberReceived on Tue Mar 04 2014 - 00:30:02 PST