Just checking if anyone has experienced a similar situation or has any pointers to understand this.
Thank you Saliya On Jul 1, 2015 9:27 PM, "Saliya Ekanayake" <esal...@gmail.com> wrote: > Hi, > > I am getting strange performance results for allgatherv operation for the > same number of procs and data, but with varying binding width. For example > here are two cases with about 180x difference in performance. > > Each machine has 4 sockets each with 6 cores totaling 24 cores per node > (topology attached). > > Case 1 > ---- > 12 procs per node each bound to 1 core times 30 nodes --> 1929 ms > > Case 2 > ---- > 12 procs per node each bound to 2 cores times 30 nodes --> 357209 ms > > > Another set of variations for 2 procs per node and 4 procs per node is > given below in the chart. Is such variation expected with binding width? I > am a bit puzzled and would appreciate any help to understand this. > > [image: Inline image 1] > > Thank you, > Saliya > > -- > Saliya Ekanayake > Ph.D. Candidate | Research Assistant > School of Informatics and Computing | Digital Science Center > Indiana University, Bloomington > Cell 812-391-4914 > http://saliya.org >
