I have a problem with rrd graps - they look different every time.
For example: these are 2 graphs generated one by one using the same function.
My rrd_graph options looks like this:
"--slope-mode",
"--start", $start,
"--font=DEFAULT:9:Cantarell",
"--font=TITLE:12:Roboto Condensed",
"--font=AXIS:8:Roboto Condensed",
"--font=LEGEND:9:Cantarell",
"--font=WATERMARK:6:Cantarell",
"--title=$title",
"-W General",
"--vertical-label=Tx[dBm] / Rx[dBm] / SNR[dB]",
"--lower=0",
"-w 550",
"-h 300",
"-P",
"--border=0",
"--color=BACK#ffffff",
"DEF:Tx=$RRD_CM_PATH$cm_mac_mod.rrd:US_Tx:AVERAGE",
"DEF:SNR=$RRD_CM_PATH$cm_mac_mod.rrd:US_SNR:AVERAGE",
"DEF:Rx=$RRD_CM_PATH$cm_mac_mod.rrd:US_Rx:AVERAGE",
"COMMENT:\\n",
"COMMENT:\\t\\t\\t\\t\\t\\t\\t\\t Current\\t\\t Average\\t\\tMinimum\\t Maximum",
"COMMENT:\\n",
"COMMENT:\\t\\t\\t",
"LINE3:Tx#055499:US Tx\\t\\t\\t",
"GPRINT:Tx:LAST:%2.1lfdBm \\t",
"GPRINT:Tx:AVERAGE:%2.1lfdBm \\t",
"GPRINT:Tx:MAX:%2.1lfdBm \\t",
"GPRINT:Tx:MIN:%2.1lfdBm \\t",
"COMMENT:\\n",
"COMMENT:\\t\\t\\t",
"LINE3:SNR#ff5a00:US SNR\\t\\t",
"GPRINT:SNR:LAST:%2.1lfdBm\\t",
"GPRINT:SNR:AVERAGE:%2.1lfdBm\\t",
"GPRINT:SNR:MAX:%2.1lfdBm\\t",
"GPRINT:SNR:MIN:%2.1lfdBm\\t",
"COMMENT:\\n",
"COMMENT:\\t\\t\\t",
"LINE3:Rx#4be117:US_Rx\\t",
"GPRINT:Rx:LAST:%2.1lfdBm\\t",
"GPRINT:Rx:AVERAGE:%2.1lfdBm\\t",
"GPRINT:Rx:MAX:%2.1lfdBm\\t",
"GPRINT:Rx:MIN:%2.1lfdBm\\t",
"COMMENT:\\n",