diff --git a/orte/mca/ras/slurm/ras_slurm.h b/orte/mca/ras/slurm/ras_slurm.h
index 50f601e5cf..9dd7b93e01 100644
--- a/orte/mca/ras/slurm/ras_slurm.h
+++ b/orte/mca/ras/slurm/ras_slurm.h
@@ -11,6 +11,7 @@
  *                         All rights reserved.
  * Copyright (c) 2012-2013 Los Alamos National Security, LLC.
  *                         All rights reserved.
+ * Copyright (c) 2015      Intel, Inc. All rights reserved.
  * $COPYRIGHT$
  * 
  * Additional copyrights may follow
@@ -37,6 +38,7 @@ typedef struct {
     bool dyn_alloc_enabled;
     char *config_file;
     bool rolling_alloc;
+    bool use_all;
 } orte_ras_slurm_component_t;
 ORTE_DECLSPEC extern orte_ras_slurm_component_t mca_ras_slurm_component;
 
diff --git a/orte/mca/ras/slurm/ras_slurm_component.c b/orte/mca/ras/slurm/ras_slurm_component.c
index 3667560c52..2eb47b5366 100644
--- a/orte/mca/ras/slurm/ras_slurm_component.c
+++ b/orte/mca/ras/slurm/ras_slurm_component.c
@@ -106,6 +106,14 @@ static int ras_slurm_register(void)
                                             MCA_BASE_VAR_SCOPE_READONLY,
                                             &mca_ras_slurm_component.rolling_alloc);
 
+    mca_ras_slurm_component.use_all = false;
+    (void) mca_base_component_var_register (component, "use_entire_allocation",
+                                            "Use entire allocation (not just job step nodes) for this application",
+                                            MCA_BASE_VAR_TYPE_BOOL, NULL, 0, 0,
+                                            OPAL_INFO_LVL_9,
+                                            MCA_BASE_VAR_SCOPE_READONLY,
+                                            &mca_ras_slurm_component.use_all);
+
     return ORTE_SUCCESS;
 }
 
diff --git a/orte/mca/ras/slurm/ras_slurm_module.c b/orte/mca/ras/slurm/ras_slurm_module.c
index 5221d0973b..a90fe9b44c 100644
--- a/orte/mca/ras/slurm/ras_slurm_module.c
+++ b/orte/mca/ras/slurm/ras_slurm_module.c
@@ -280,39 +280,63 @@ static int orte_ras_slurm_allocate(orte_job_t *jdata, opal_list_t *nodes)
         ORTE_ERROR_LOG(ORTE_ERR_OUT_OF_RESOURCE);
         return ORTE_ERR_OUT_OF_RESOURCE;
     }
-    
-    /* get the number of process slots we were assigned on each node */
-    tasks_per_node = getenv("SLURM_TASKS_PER_NODE");
-    if (NULL == tasks_per_node) {
-        /* couldn't find any version - abort */
-        orte_show_help("help-ras-slurm.txt", "slurm-env-var-not-found", 1,
-                       "SLURM_TASKS_PER_NODE");
-        free(regexp);
-        return ORTE_ERR_NOT_FOUND;
-    }
-    node_tasks = strdup(tasks_per_node);
-    if(NULL == node_tasks) {
-        ORTE_ERROR_LOG(ORTE_ERR_OUT_OF_RESOURCE);
-        free(regexp);
-        return ORTE_ERR_OUT_OF_RESOURCE;
-    }
 
-    /* get the number of CPUs per task that the user provided to slurm */
-    tmp = getenv("SLURM_CPUS_PER_TASK");
-    if(NULL != tmp) {
-        cpus_per_task = atoi(tmp);
-        if(0 >= cpus_per_task) {
-            opal_output(0, "ras:slurm:allocate: Got bad value from SLURM_CPUS_PER_TASK. "
-                        "Variable was: %s\n", tmp);
-            ORTE_ERROR_LOG(ORTE_ERROR);
-            free(node_tasks);
+    if (mca_ras_slurm_component.use_all) {
+        /* this is an oddball case required for debug situations where
+         * a tool is started that will then call mpirun. In this case,
+         * Slurm will assign only 1 tasks/per node to the tool, but
+         * we want mpirun to use the entire allocation. They don't give
+         * us a specific variable for this purpose, so we have to fudge
+         * a bit - but this is a special edge case, and we'll live with it */
+        tasks_per_node = getenv("SLURM_JOB_CPUS_PER_NODE");
+        if (NULL == tasks_per_node) {
+            /* couldn't find any version - abort */
+            orte_show_help("help-ras-slurm.txt", "slurm-env-var-not-found", 1,
+                           "SLURM_JOB_CPUS_PER_NODE");
             free(regexp);
-            return ORTE_ERROR;
+            return ORTE_ERR_NOT_FOUND;
+        }
+        node_tasks = strdup(tasks_per_node);
+        if (NULL == node_tasks) {
+            ORTE_ERROR_LOG(ORTE_ERR_OUT_OF_RESOURCE);
+            free(regexp);
+            return ORTE_ERR_OUT_OF_RESOURCE;
         }
-    } else {
         cpus_per_task = 1;
+    } else {
+        /* get the number of process slots we were assigned on each node */
+        tasks_per_node = getenv("SLURM_TASKS_PER_NODE");
+        if (NULL == tasks_per_node) {
+            /* couldn't find any version - abort */
+            orte_show_help("help-ras-slurm.txt", "slurm-env-var-not-found", 1,
+                           "SLURM_TASKS_PER_NODE");
+            free(regexp);
+            return ORTE_ERR_NOT_FOUND;
+        }
+        node_tasks = strdup(tasks_per_node);
+        if (NULL == node_tasks) {
+            ORTE_ERROR_LOG(ORTE_ERR_OUT_OF_RESOURCE);
+            free(regexp);
+            return ORTE_ERR_OUT_OF_RESOURCE;
+        }
+
+        /* get the number of CPUs per task that the user provided to slurm */
+        tmp = getenv("SLURM_CPUS_PER_TASK");
+        if(NULL != tmp) {
+            cpus_per_task = atoi(tmp);
+            if(0 >= cpus_per_task) {
+                opal_output(0, "ras:slurm:allocate: Got bad value from SLURM_CPUS_PER_TASK. "
+                            "Variable was: %s\n", tmp);
+                ORTE_ERROR_LOG(ORTE_ERROR);
+                free(node_tasks);
+                free(regexp);
+                return ORTE_ERROR;
+            }
+        } else {
+            cpus_per_task = 1;
+        }
     }
- 
+    
     ret = orte_ras_slurm_discover(regexp, node_tasks, nodes);
     free(regexp);
     free(node_tasks);