The plotPerf function

Chapter 4.3 : The plotPerf function

This function has to create a Gnuplot file to make plots with the different input target we want to compare. This will ensure us to compare the performances we want.

Two plots are relevant in our case :

The total number of cycle of the computation : important to be sure that the computation is well done. If the number of computed elements increases but the total elapsed time is decreasing, there is a problem !
The number of cycle spend to compute one single element : useful to get precise imformation about the optimisations we are doing.

function(plotPerf baseOutputPng)
	set(GNUPLOT_FILE "${OUTPUT_PERF_DIR}/${baseOutputPng}.gnuplot")
	file(WRITE ${GNUPLOT_FILE} "set terminal png notransparent crop enhanced size 800,600 font \"arial,14\"\n")
	file(APPEND ${GNUPLOT_FILE} "set grid xtics ytics mytics\n")
	file(APPEND ${GNUPLOT_FILE} "set key bottom right\n")
	file(APPEND ${GNUPLOT_FILE} "set logscale y\n")
	file(APPEND ${GNUPLOT_FILE} "set xlabel \"nb elements\"\n")
	file(APPEND ${GNUPLOT_FILE} "set ylabel \"elapsed time per element [cy/el]\"\n")
	file(APPEND ${GNUPLOT_FILE} "set output \"${baseOutputPng}ElapsedTimeCyEl.png\"\n")
	file(APPEND ${GNUPLOT_FILE} "plot ")
	
	set(listDepend)
	foreach(inputTarget ${ARGN})
		string(REPLACE "_" " " legendStr ${inputTarget})
		file(APPEND ${GNUPLOT_FILE} "\"${inputTarget}.txt\" using 1:2 title \"${legendStr}\" with lines  lw 2,")
		list(APPEND listDepend "${OUTPUT_PERF_DIR}/${inputTarget}.txt")
	endforeach(inputTarget)
	file(APPEND ${GNUPLOT_FILE} "\n")
	
	file(APPEND ${GNUPLOT_FILE} "set xlabel \"nb elements\"\n")
	file(APPEND ${GNUPLOT_FILE} "set ylabel \"elapsed time [cy]\"\n")
	file(APPEND ${GNUPLOT_FILE} "set output \"${baseOutputPng}ElapsedTime.png\"\n")
	file(APPEND ${GNUPLOT_FILE} "plot ")
	
	foreach(inputTarget ${ARGN})
		string(REPLACE "_" " " legendStr ${inputTarget})
		file(APPEND ${GNUPLOT_FILE} "\"${inputTarget}.txt\" using 1:3 title \"${legendStr}\" with lines  lw 2,")
	endforeach(inputTarget)
	file(APPEND ${GNUPLOT_FILE} "\n")
	
	add_custom_command(OUTPUT ${OUTPUT_PERF_DIR}/${baseOutputPng}ElapsedTimeCyEl.png ${OUTPUT_PERF_DIR}/${baseOutputPng}ElapsedTime.png
		COMMAND gnuplot  ${GNUPLOT_FILE}
		WORKING_DIRECTORY "${OUTPUT_PERF_DIR}"
		COMMENT "Call gnuplot ${baseOutputPng}"
		DEPENDS ${listDepend}
	)
	add_custom_target("plot_${baseOutputPng}"  DEPENDS ${OUTPUT_PERF_DIR}/${baseOutputPng}ElapsedTimeCyEl.png ${OUTPUT_PERF_DIR}/${baseOutputPng}ElapsedTime.png)
	
	foreach(inputTarget ${ARGN})
		add_dependencies("plot_${baseOutputPng}" "run_${inputTarget}")
	endforeach(inputTarget)
	
	
	add_dependencies(plot_all "plot_${baseOutputPng}")
endfunction(plotPerf)

We can also add a function for the very end of the tutorial :

function(plotPerfProba baseOutputPng)
	set(GNUPLOT_FILE "${OUTPUT_PERF_DIR}/${baseOutputPng}.gnuplot")
	file(WRITE ${GNUPLOT_FILE} "set terminal png notransparent crop enhanced size 800,600 font \"arial,14\"\n")
	file(APPEND ${GNUPLOT_FILE} "set grid xtics ytics mytics\n")
	file(APPEND ${GNUPLOT_FILE} "set key bottom right\n")
	file(APPEND ${GNUPLOT_FILE} "set logscale y\n")
	file(APPEND ${GNUPLOT_FILE} "set xlabel \"proba\"\n")
	file(APPEND ${GNUPLOT_FILE} "set ylabel \"elapsed time per element [cy/el]\"\n")
	file(APPEND ${GNUPLOT_FILE} "set output \"${baseOutputPng}ElapsedTimeCyEl.png\"\n")
	file(APPEND ${GNUPLOT_FILE} "plot ")
	
	set(listDepend)
	foreach(inputTarget ${ARGN})
		string(REPLACE "_" " " legendStr ${inputTarget})
		file(APPEND ${GNUPLOT_FILE} "\"${inputTarget}.txt\" using 1:2 title \"${legendStr}\" with lines  lw 2,")
		list(APPEND listDepend "${OUTPUT_PERF_DIR}/${inputTarget}.txt")
	endforeach(inputTarget)
	file(APPEND ${GNUPLOT_FILE} "\n")
	
	file(APPEND ${GNUPLOT_FILE} "set xlabel \"proba\"\n")
	file(APPEND ${GNUPLOT_FILE} "set ylabel \"elapsed time [cy]\"\n")
	file(APPEND ${GNUPLOT_FILE} "set output \"${baseOutputPng}ElapsedTime.png\"\n")
	file(APPEND ${GNUPLOT_FILE} "plot ")
	
	foreach(inputTarget ${ARGN})
		string(REPLACE "_" " " legendStr ${inputTarget})
		file(APPEND ${GNUPLOT_FILE} "\"${inputTarget}.txt\" using 1:3 title \"${legendStr}\" with lines  lw 2,")
	endforeach(inputTarget)
	file(APPEND ${GNUPLOT_FILE} "\n")
	
	add_custom_command(OUTPUT ${OUTPUT_PERF_DIR}/${baseOutputPng}ElapsedTimeCyEl.png ${OUTPUT_PERF_DIR}/${baseOutputPng}ElapsedTime.png
		COMMAND gnuplot  ${GNUPLOT_FILE}
		WORKING_DIRECTORY "${OUTPUT_PERF_DIR}"
		COMMENT "Call gnuplot ${baseOutputPng}"
		DEPENDS ${listDepend}
	)
	add_custom_target("plot_${baseOutputPng}"  DEPENDS ${OUTPUT_PERF_DIR}/${baseOutputPng}ElapsedTimeCyEl.png ${OUTPUT_PERF_DIR}/${baseOutputPng}ElapsedTime.png)
	foreach(inputTarget ${ARGN})
		add_dependencies("plot_${baseOutputPng}" "run_${inputTarget}")
	endforeach(inputTarget)
	add_dependencies(plot_all "plot_${baseOutputPng}")
endfunction(plotPerfProba)