mem.gplot
set title "Memory Utilization"
set ylabel "MB"
plot \
datafile using 3:($5/1024) title 'Used' with filledcurves x1, \
datafile using 3:($5/1024) notitle with lines lc rgb "#000000" lw 1, \
datafile using 3:(($5 - $7 - $8)/1024) title 'Really Used' with filledcurves x1, \
datafile using 3:(($5 - $7 - $8)/1024) notitle with lines lc rgb "#000000" lw 1