64 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			64 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
This directory contains tools to profile the sdcard performance.
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There are 2 parts to the tool:
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* A binary that runs on the device, exercises the sdcard and send
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  measurment data back to the host (sdcard_perf_test).
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* A host python script to plot the data.
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Additionally, there is script 'profile_sdcard.sh' that allows you
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to check how the sdcard scale with the number of processes.
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INSTALLATION
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============
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Build, install and mount debugfs. In this directory with a properly
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configured enviroment:
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  mm SDCARD_TESTS=1
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  adb remount
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  adb push $ANDROID_PRODUCT_OUT/system/bin/sdcard_perf_test /system/bin/sdcard_perf_test
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  adb shell mount -t debugfs none /sys/kernel/debug
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If you want to graph the results you need gnuplot and numpy:
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  sudo apt-get install gnuplot python-numpy python-numeric
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You need Gnuplot.py version 1.8 (not the one coming with ubuntu).
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Download it from the Gnuplot.py web site.  Extract to a temp
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directory, chdir and run:
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  sudo python setup.py install
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INVOCATION
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==========
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Run a simple test:
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  adb shell sdcard_perf_test --test=write --size=1000 --chunk-size=100 --procnb=1 --iterations=100
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This test will write 1000kbyte (1M) files using writes of 100kbytes (so 10 writes per file) using
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only 1 process for 100 times (100 files will be written on the sdcard).
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The test will not call sync to flush the writes.
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At the end of the test, some stats for the 'open' and 'write' system calls are written.
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If you want to plot the data, you need to use the --dump option and provide a file:
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  adb shell sdcard_perf_test --test=write --size=1000 --chunk-size=100 --procnb=1 --iterations=100 --dump >/tmp/data.txt
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PLOTTING
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========
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To plot the result using the iter number of the x axis:
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  plot_sdcard.py -i /tmp/data.txt
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To plot the result using time for the x axis:
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  plot_sdcard.py -t /tmp/data.txt
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To plot the result from the profiler:
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    profile_sdcard.sh
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    plot_sdcard.py -p
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