As I think it's not relevant to Open MPI itself, I answered in PM only. -- Reuti
> Am 18.05.2017 um 18:55 schrieb do...@mail.com: > > On Tue, 9 May 2017 00:30:38 +0200 > Reuti <re...@staff.uni-marburg.de> wrote: >> Hi, >> >> Am 08.05.2017 um 23:25 schrieb David Niklas: >> >>> Hello, >>> I originally ported this question at LQ, but the answer I got back >>> shows rather poor insight on the subject of MPI, so I'm taking the >>> liberty of posting here also. >>> >>> https://www.linuxquestions.org/questions/showthread.php?p=5707962 >>> >>> What I'm trying to do is figure out how/what to use to update an osm >>> file (open street map), in a cross system manner. I know the correct >>> program osmosis and for de/re-compression lbzip2 but how to do this >>> across computers is confusing me, even after a few hours of searching >>> online. >> >> lbzip2 is only thread parallel on a single machine. With pbzip2 you >> mention it's the same, but it exists an MPI version MPIBZIP2 - > I can't find the project, do you have a link? > >> unfortunately it looks unmaintained since 2007. Maybe you can contact >> the author about its state. Without an MPI application like this, the >> MPI library is nothing on its own which would divide and distribute one >> task to several machines automatically. > Well, there might be other ways to cause a program to run on multiple > computers. Perhaps a virtual machine made of of multiple physical > machines? > >> osmosis itself seems to run in serial only (they don't say any word >> whether it uses any parallelism). > Yes, it does run multiple threads, you just start another task (and add a > buffer). I tested this on my machine, I think it is --read-xml > --write-xml and --read-xml-change that start new threads. The question is > whether or not java is naively MPI aware or does the app need special > coding? > >> For the intended task the only option is to use a single machine with >> as many cores as possible AFAICS. > Though about that, and it is doable with respect to memory and disk > constraints, the problem is that it would take a *long* time esp. with the > amount of updates I must do, hence my inquiry. > > Thanks, > David > _______________________________________________ > users mailing list > users@lists.open-mpi.org > https://rfd.newmexicoconsortium.org/mailman/listinfo/users _______________________________________________ users mailing list users@lists.open-mpi.org https://rfd.newmexicoconsortium.org/mailman/listinfo/users
