Hi Ralph, thank you for the advice.
You are right, the deamon is NOT MPI processes. I would like to use the Open MPI I/O module to implement. In my opinion, the commends sent by the client will start an MPI I/O operation, therefore, the client can start an MPI process. In addition, I have found a similar "select logic" module in the OMPIO, which is a new MPI I/O architecture in Open MPI (besides the ROMIO). Therefore, the whole process from "client call" to "returning result" is an MPI process, if I have not made a mistake. Best Regards! Xuan ----- Original Message ----- From: "Ralph Castain" <r...@open-mpi.org> To: "Open MPI Users" <us...@open-mpi.org> Sent: Wednesday, June 13, 2012 2:44:31 PM Subject: Re: [OMPI users] An idea about a semi-automatic optimized parallel I/O with Open MPI One flaw in the idea: the daemons are not MPI processes, and therefore have no way to run an MPI I/O operation. On Jun 13, 2012, at 5:40 AM, Xuan Wang wrote: > Hi, > > I have an idea about using database to support a kind of semi-automatic > optimized parallel I/O operations and want to know if it is realizable or > not. Hope you guys can give me more advices and point out the shortage of the > idea. Thank you all. > > As the performance of the parallel I/O depends on the parallel I/O algorithm, > the file storage in file system, the number of processes used for I/O and so > on, we can use the MPI hints to control the parameters manually. But > sometime, the client or the people who call the I/O operation don’t know > which parameters are the best. > > Therefore, we think about using the data warehouse and an I/O monitor to > realize the optimization phase. Please take a look at the attached picture > first. > > Process explanations: > 1. The client sends the I/O commends with hints (optional) to deamon. The > select model will decide if it is necessary to call the I/O database in order > to get the optimized I/O operation strategy. > 2. If yes, the select model sends the I/O commends with those parameters, > which can be used to choose the optimized I/O algorithm, to the knowledge > base or database. > 3 & 4. The select model gets the optimized algorithm and runs the I/O > operation. > 5 & 6. During the I/O operation, the monitor will gather the performance > related information and sends it to the data warehouse, which is used to > analyze the performance of the optimized algorithm and support the > semi-automatic optimization. > > These are the basic thought about the whole process. Please be free to ask > any details about this system/concept. I will try my best to explain it. > > I am happy if someone can take part in the discussion. > > Thanks! > > Best Regards! > Xuan Wang<1.PNG>_______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users _______________________________________________ users mailing list us...@open-mpi.org http://www.open-mpi.org/mailman/listinfo.cgi/users
