From 6c9d094755bdf96ab1c8fe28c5be86f5c7bfa58c Mon Sep 17 00:00:00 2001 From: James Willis <james.s.willis@durham.ac.uk> Date: Wed, 27 Jan 2016 16:09:46 +0000 Subject: [PATCH] Changed the cell_max_tag to 2^29 to prevent MPI tag collisions. --- src/cell.h | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/src/cell.h b/src/cell.h index d5d8b5db8b..96be24688a 100644 --- a/src/cell.h +++ b/src/cell.h @@ -29,7 +29,12 @@ struct space; /* Some constants. */ #define cell_sid_dt 13 -#define cell_max_tag (1 << 16) + +/* Max tag size set to 2^29 to take into account some MPI implementations + * that use 2^31 as the upper bound on MPI tags and the fact that + * cell_next_tag is multiplied by 2 when passed to an MPI function. + * The maximum was lowered by a further factor of 2 to be on the safe side.*/ +#define cell_max_tag (1 << 29) /* Global variables. */ extern int cell_next_tag; -- GitLab