diff --git a/garlic/pp/timetable.nix b/garlic/pp/timetable.nix
index 586d407..0f2e18b 100644
--- a/garlic/pp/timetable.nix
+++ b/garlic/pp/timetable.nix
@@ -20,11 +20,14 @@ stdenv.mkDerivation {
         conf=garlic_config.json
         for run in $(ls -d [0-9]* | sort -n); do
           time=$(awk '/^ ?time /{print $2}' $run/stdout.log)
+          if [ -z "$time" ]; then
+            echo "error: cannot match \"time\" line
+            echo "check stdout log file: ${inputResult}/$exp/$unit/$run/stdout.log"
+            exit 1
+          fi
           jq -cn "{ exp:\"$exp\", unit:\"$unit\", config:inputs, time:$time, run:$run }" $conf >> $out
         done
       done
     done
-
-    #gzip $out
   '';
 }