This is an artifact of using the gatherv (or the scatterv) on an inter-communicator without any useful data (i.e. either count of zero or empty datatypes). Looks more like a synchronization than a real operation.
george. On May 5, 2010, at 20:17 , Lisandro Dalcin wrote: > After building 1.4.2 with debug flags to configure, I get this (I've > got these warnings in previous releases, too): > > malloc debug: Request for 0 bytes (coll_inter_gatherv.c, 94) > malloc debug: Request for 0 bytes (coll_inter_gatherv.c, 94) > malloc debug: Request for 0 bytes (coll_inter_gatherv.c, 94) > malloc debug: Request for 0 bytes (coll_inter_gatherv.c, 94) > > malloc debug: Request for 0 bytes (coll_inter_scatterv.c, 82) > malloc debug: Request for 0 bytes (coll_inter_scatterv.c, 82) > malloc debug: Request for 0 bytes (coll_inter_scatterv.c, 82) > malloc debug: Request for 0 bytes (coll_inter_scatterv.c, 82) > > > -- > Lisandro Dalcin > --------------- > CIMEC (INTEC/CONICET-UNL) > Predio CONICET-Santa Fe > Colectora RN 168 Km 472, Paraje El Pozo > Tel: +54-342-4511594 (ext 1011) > Tel/Fax: +54-342-4511169 > _______________________________________________ > devel mailing list > de...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/devel
