1 files changed, 13 insertions, 0 deletions

diff --git a/src/pruning.c b/src/pruning.c
index d484a12..869110f 100644
--- a/src/pruning.c
+++ b/src/pruning.c
@@ -135,6 +135,18 @@ genptable(PruneData *pd, int nthreads)
                 return;
         }
 
+        if (nthreads < 4) {
+                fprintf(stderr,
+                        "--- Warning ---\n"
+                        "You are using only %d threads to generate the pruning"
+                        "tables. This can take a while."
+                        "Unless you did this intentionally, you should re-run"
+                        "this command with `-t 4' or more.\n"
+                        "---------------\n\n", nthreads
+                );
+        }
+
+
         /* For the first steps we proceed the same way for compact and not */
         compact = pd->compact;
         pd->compact = false;
@@ -144,6 +156,7 @@ genptable(PruneData *pd, int nthreads)
         fprintf(stderr, "Cannot load %s, generating it with %d threads\n",
                         pd->filename, nthreads); 
 
+
         memset(pd->ptable, ~(uint8_t)0, ptablesize(pd)*sizeof(entry_group_t));
 
         ptable_update(pd, (Cube){0}, 0);