diff --git a/oldies/rrd-resize-double.sh b/oldies/rrd-resize-double.sh
new file mode 100755
index 0000000..c81e1a2
--- /dev/null
+++ b/oldies/rrd-resize-double.sh
@@ -0,0 +1,45 @@
+#!/bin/sh
+
+# This script simply takes a rrd file and doubles the rows of all its RRA
+#
+# Result in tmp.rrd
+#
+# Make backups before any important use !
+
+RESULT_FILENAME="result.rrd"
+
+set -e
+
+if [ ! -f "$1" ]; then
+	echo "ERROR: no file specified." >&2
+	exit 1
+fi
+
+SRC="$1"
+DST="$( dirname "$SRC" )/$RESULT_FILENAME"
+# rrdtool seems to always create in current directory
+RRD_SPECIAL_FILE="resize.rrd"
+
+if [ -f "$RRD_SPECIAL_FILE" ] || [ -f "$DST" ]; then
+	echo "ERROR: files with names '$RRD_SPECIAL_FILE' or '$DST' already exist. Trouble ?" >&2
+	exit 1
+fi
+
+# Initial copy
+cp -ai "$SRC" "$DST"
+
+# Only use the SRC for enumeration : all the work after that is done on DST
+rrdtool info "$SRC" | grep rows | while read LINE; do
+	RRANUM="$( echo "$LINE" | sed 's/.*\[\([0-9]\+\)\].rows.*/\1/' )"
+	ROWS="$( echo "$LINE" | sed 's/.* = //' )"
+	if [ -z "$RRANUM" ] || [ -z "$ROWS" ]; then
+		echo "Trouble at the mill." >&2
+		exit 2
+	fi
+
+	rrdtool resize "$DST" $RRANUM GROW $ROWS && mv "$RRD_SPECIAL_FILE" "$DST"
+done
+
+# I often forget this one...
+chmod "--reference=$SRC" "$DST"
+chown "--reference=$SRC" "$DST"