From 567b40b9a97703e501fe67df081a6d4167ff7423 Mon Sep 17 00:00:00 2001 From: Jelena Pjesivac-Grbovic Date: Tue, 26 Jun 2007 20:08:31 +0000 Subject: [PATCH] Modifying the default broadcast decision function to use binomial algorithm for single-element broadcasts (segmented algorithms make no sense in this case and can cause performance degradation). This commit was SVN r15208. --- ompi/mca/coll/tuned/coll_tuned_decision_fixed.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/ompi/mca/coll/tuned/coll_tuned_decision_fixed.c b/ompi/mca/coll/tuned/coll_tuned_decision_fixed.c index b830dd32f8..9cd1492b7c 100644 --- a/ompi/mca/coll/tuned/coll_tuned_decision_fixed.c +++ b/ompi/mca/coll/tuned/coll_tuned_decision_fixed.c @@ -225,8 +225,9 @@ int ompi_coll_tuned_bcast_intra_dec_fixed(void *buff, int count, " root %d rank %d com_size %d msg_length %lu", root, rank, communicator_size, (unsigned long)message_size)); - /* Handle messages of small and intermediate size */ - if (message_size < small_message_size) { + /* Handle messages of small and intermediate size, and + single-element broadcasts */ + if ((message_size < small_message_size) || (count <= 1)) { /* Binomial without segmentation */ segsize = 0; return ompi_coll_tuned_bcast_intra_binomial (buff, count, datatype,