diff --git a/tools/plot.sh b/tools/plot.sh
index b2a1302..ea046a7 100755
--- a/tools/plot.sh
+++ b/tools/plot.sh
@@ -22,9 +22,13 @@ jq  -r '.Cycles[]| [.C,.L1,.VDI]|@csv' -- "$IN" > "$CSV_FILE"
 
 BASE_GNUPLOT_OPTIONS="set datafile separator ',';set term svg;set output \"${OUT}\";"
 
+parse_cache_size(){
+	CACHE_SIZE=$(jq -r .L1_size -- "$IN")
+}
+
 case "$2" in
 	"cache_time")
-		CACHE_SIZE=$(jq -r .L1_size -- "$IN")
+		parse_cache_size
 		gnuplot -e "${BASE_GNUPLOT_OPTIONS}\
 set xlabel \"Clock cycles\";\
 set ylabel \"Cache utilisation (bytes)\";\
@@ -32,13 +36,15 @@ set offsets 0,  0, 3, 1;\
 set ytics 0,1,$((CACHE_SIZE-1));\
 unset colorbox;\
 set ytics add (\"Valid\" -1);\
+set grid ytics;\
+set yrange [-2:${CACHE_SIZE}];\
 set palette model RGB defined ( 0 'red', 1 'green' );\
-plot '${CSV_FILE}' using 1:2  with lines notitle ,\
+plot '${CSV_FILE}' using 1:2  with histeps notitle ,\
      '${CSV_FILE}' using 1:(-0.75):(0):(-0.5):3 with vectors nohead palette notitle"
 
 		;;
 	"cache_util_freq")
-		CACHE_SIZE=$(jq -r .L1_size -- "$IN")
+		parse_cache_size
 		gnuplot -e "${BASE_GNUPLOT_OPTIONS}\
 set xlabel \"Utilisation (bytes)\";\
 set ylabel \"Occurrences\";\