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+This version of init contains code to perform "bootcharting", i.e. generating log
+files that can be later processed by the tools provided by www.bootchart.org.
+
+To activate it, you need to define build 'init' with the INIT_BOOTCHART environment
+variable defined to 'true', for example:
+
+ touch system/init/init.c
+ m INIT_BOOTCHART=true
+
+On the emulator, use the new -bootchart <timeout> option to boot with bootcharting
+activated for <timeout> seconds.
+
+Otherwise, flash your device, and start it. Then create a file on the /data partition
+with a command like the following:
+
+ adb shell 'echo $TIMEOUT > /data/bootchart-start'
+
+Where the value of $TIMEOUT corresponds to the wanted bootcharted period in seconds;
+for example, to bootchart for 2 minutes, do:
+
+ adb shell 'echo 120 > /data/bootchart-start'
+
+Reboot your device, bootcharting will begin and stop after the period you gave.
+You can also stop the bootcharting at any moment by doing the following:
+
+ adb shell 'echo 1 > /data/bootchart-stop'
+
+Note that /data/bootchart-stop is deleted automatically by init at the end of the
+bootcharting. This is not the case of /data/bootchart-start, so don't forget to delete it
+when you're done collecting data:
+
+ adb shell rm /data/bootchart-start
+
+The log files are placed in /data/bootchart/. you must run the script tools/grab-bootchart.sh
+which will use ADB to retrieve them and create a bootchart.tgz file that can be used with
+the bootchart parser/renderer, or even uploaded directly to the form located at:
+
+ http://www.bootchart.org/download.html
+
+NOTE: the bootchart.org webform doesn't seem to work at the moment, you can generate an
+ image on your machine by doing the following:
+
+ 1/ download the sources from www.bootchart.org
+ 2/ unpack them
+ 3/ in the source directory, type 'ant' to build the bootchart program
+ 4/ type 'java -jar bootchart.jar /path/to/bootchart.tgz
+
+technical note:
+
+this implementation of bootcharting does use the 'bootchartd' script provided by
+www.bootchart.org, but a C re-implementation that is directly compiled into our init
+program.