Marion, OSCAR is a system management tool: it allows one to deploy and manage a cluster, focusing on the system software. A cluster is typically composed of: - a batch system/resource manager for the allocation of resources (CPUs typically) for your application, its deployment and it execution, - some library/runtime for parallel applications (such as MPI).
OSCAR does not deal by default with the installation of your application. So you typically have two situations: - Your application is sequential, then you do data parallelism: each entity of the application is running the same code but since your input is different, so you have parallelism. - Your application is parallel in nature, e.g., an MPI appliction: the application describes explicitely the communications inside the application between each parallel piece. Does it help? Regards, ----- Mail Original ----- De: "Marion Randall" <ranmar...@gmail.com> À: oscar-users@lists.sourceforge.net Envoyé: Mercredi 10 Juin 2009 02h29:48 GMT -05:00 USA/Canada - États de l'Est Objet: Re: [Oscar-users] Just a little theoretical question about OSCAR Hi ! Joe, I don't have the faintest idea whether the chemical program uses MPI directly or indirectly or not at all. The application uses the program Linda, and I don't know the details of Linda. Menjuei, I think I'm beginning to see where my reasoning was utterly crooked. To know how a job is distributed across the cluster, I should look at the programs that OSCAR installs, and not at OSCAR itself, since that is not what OSCAR is intended for. Am I closer to the truth? Someone that I know built a cluster without using OSCAR (or Rocks) and he was saying things about OSCAR that I wanted to verify. However, it is quite plain to me now that either he was generalizing and meaning the job scheduler and queuing software when he actually said "OSCAR", or he is really not as knowledgeable as he makes himself out to be. Thus, I'm quite satisfied with the answer that I've received so far about my perception being completely off the mark, and since I don't want to waste anyone else's time any further, I will go and do some googling and additional reading on my own. As for me, I am greatly indebted to the people who have developed OSCAR. Just imagine someone as clueless as myself trying to build a cluster from scratch... Not good for the environment. ;-) Thanks for helping me! 2009/6/9 Greenseid, Joseph M (IS) < joseph.greens...@ngc.com > Does your chemical app use MPI? --Joe From: Marion Randall [mailto: ranmar...@gmail.com ] Sent: Tue 6/9/2009 3:26 PM To: oscar-users@lists.sourceforge.net Subject: [Oscar-users] Just a little theoretical question about OSCAR Hi! On my cluster I am running a chemical application. Am I right in saying that : OSCAR dishes out pieces of the chemical program (that can be parallelized) from the headnode to the compute nodes, and then the compute nodes calculate their chunk of computations and send it back to the headnode. This process repeats itself as many times as is possible and necessary, but the compute nodes always communicate to the headnode and not to each other? Please correct my above reasoning if it's wrong. Thank you! :-) Rion -- "O wretched man that I am! Who will deliver me from this body of death? I thank God - through Jesus Christ our Lord! So then, with the mind I myself serve the law of God, but with the flesh the law of sin." Rom.7:24-25 ------------------------------------------------------------------------------ Crystal Reports - New Free Runtime and 30 Day Trial Check out the new simplified licensing option that enables unlimited royalty-free distribution of the report engine for externally facing server and web deployment. http://p.sf.net/sfu/businessobjects _______________________________________________ Oscar-users mailing list Oscar-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/oscar-users -- "O wretched man that I am! Who will deliver me from this body of death? I thank God - through Jesus Christ our Lord! So then, with the mind I myself serve the law of God, but with the flesh the law of sin." Rom.7:24-25 ------------------------------------------------------------------------------ Crystal Reports - New Free Runtime and 30 Day Trial Check out the new simplified licensing option that enables unlimited royalty-free distribution of the report engine for externally facing server and web deployment. http://p.sf.net/sfu/businessobjects _______________________________________________ Oscar-users mailing list Oscar-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/oscar-users ------------------------------------------------------------------------------ Crystal Reports - New Free Runtime and 30 Day Trial Check out the new simplified licensing option that enables unlimited royalty-free distribution of the report engine for externally facing server and web deployment. http://p.sf.net/sfu/businessobjects _______________________________________________ Oscar-users mailing list Oscar-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/oscar-users
