diff --git a/src/mpid/ch4/shm/posix/posix_coll_init.c b/src/mpid/ch4/shm/posix/posix_coll_init.c
index b1df0988405..5839f1a5b86 100644
--- a/src/mpid/ch4/shm/posix/posix_coll_init.c
+++ b/src/mpid/ch4/shm/posix/posix_coll_init.c
@@ -20,7 +20,7 @@
     - name        : MPIR_CVAR_BCAST_POSIX_INTRA_ALGORITHM
       category    : COLLECTIVE
       type        : string
-      default     : auto
+      default     : release_gather
       class       : device
       verbosity   : MPI_T_VERBOSITY_USER_BASIC
       scope       : MPI_T_SCOPE_ALL_EQ
@@ -33,7 +33,7 @@
     - name        : MPIR_CVAR_REDUCE_POSIX_INTRA_ALGORITHM
       category    : COLLECTIVE
       type        : string
-      default     : auto
+      default     : release_gather
       class       : device
       verbosity   : MPI_T_VERBOSITY_USER_BASIC
       scope       : MPI_T_SCOPE_ALL_EQ