(please reply to the list, not to me) > I hear that OpenMP is based on Shared Memory Parallel Computing, and > it needs random accessing to the data (I am not very sure, but just > hear about that, if I am wrong, please forgive me and tell me the > right thing, thanks). For my code, the contacts are stored in a list, > that is not randomly accessable. If it is ture OpenMP needs random > accessing, then how does YADE do that？Is it ok to run YADE on a > distributed memory computer architecture, like in Cluster--I saw > somebody run it on a cluster, but I do not know the cluster > architecture. Because in a distributed memory architechture, the > memory is not directlly accessable, which will increase the > programming difficulty.
Both InteractionContainer and BodyContainer support integer indices, i.e. random access. No, you cannot run yadeo n distributed memory as each core needs access to the whole memory. > Currently my speed is 3~4 second to do a iteration for about 100,000 > particles, and 33 seconds to do an iterations for 988,000 particles. > I use threads to do the parallel computing, but the speed up is only > 2.2 times faster (15 seconds for 988,000 particles.). This speed is > terrible bad, because the dt is in the order of 10^(-7) second for the > simulation of rock particles. How many cores do you have? See https://yade.hmg.inpg.fr/index.php/Speed_profiling_using_TimingInfo_and_TimingDeltas_classes to get exact idea what takes how much time (do "O.timingEnabled=True" before running the simulation, then "from yade import timing; timing.stats()" once it's over); the impact of the timing itself is in the order of a few percents. Hm, the old link looks better: http://yade.wikia.com/wiki/Speed_profiling_using_TimingInfo_and_TimingDeltas_classes It is quite possible that the collider takes a lot of time in your case. Consider using collider stride to run it only sometimes: https://yade.hmg.inpg.fr/index.php/Insertion_Sort_Collider_Stride See examples/concrete/uniax.py, search for InsertionSortCollider(sweepLength=.05*sphereRadius,nBins=5,binCoeff=5) and try if that helps. If your simulation is quasi-static, it should help a lot. Note that the initial sort in InsertionSortCollider takes very long: http://yade.wikia.com/wiki/Colliders_performace (I've been calling for a long time for a better collider, but noone took the challenge.) Cheers, Vaclav _______________________________________________ Mailing list: https://launchpad.net/~yade-users Post to : [email protected] Unsubscribe : https://launchpad.net/~yade-users More help : https://help.launchpad.net/ListHelp
