Search found 2 matches

by Lucian_Anton
Sun Feb 02, 2014 9:59 am
Forum: Computational electronic structure
Topic: OpenMP versus Posix/SystemV
Replies: 7
Views: 34118

Re: OpenMP versus Posix/SystemV

Am I correct in thinking that every process makes a call to this magical shallocate routine, even though we want a single copy of the array to be allocated per node? Thanks! Cyrus Yes, shallocate must be called by all ranks on a node and it returns an array which can be read/write by all ranks on t...
by Lucian_Anton
Sun Feb 02, 2014 9:49 am
Forum: Computational electronic structure
Topic: OpenMP versus Posix/SystemV
Replies: 7
Views: 34118

Re: OpenMP versus Posix/SystemV

Hi Cyrus, Just a quick comment to Mike description. Shared memory might need to synchronisation between the node ranks. Consider the code from bellow call shallocate(a,….) if(am_smpmaster) then read(u) a endif call shallocate_barrier ! now other ranks can access shared data b=a(i) Without the call t...