Clarify a few things about bootcharts.
Make it clearer in dmesg when we're deliberately not doing
bootcharting, and explain in the documentation that the output
for init is quite misleading (and, as far as I can tell, not
within our power to fix).
Change-Id: I0b22a56f83521d64c6d176dc423c81f7ea86b23c
diff --git a/init/readme.txt b/init/readme.txt
index 4c8d0d3..630dd03 100644
--- a/init/readme.txt
+++ b/init/readme.txt
@@ -323,12 +323,11 @@
Bootcharting
------------
-
This version of init contains code to perform "bootcharting": generating log
files that can be later processed by the tools provided by www.bootchart.org.
-On the emulator, use the new -bootchart <timeout> option to boot with
-bootcharting activated for <timeout> seconds.
+On the emulator, use the -bootchart <timeout> option to boot with bootcharting
+activated for <timeout> seconds.
On a device, create /data/bootchart/start with a command like the following:
@@ -349,9 +348,13 @@
bootchart command-line utility:
sudo apt-get install pybootchartgui
- ANDROID_SERIAL=<device serial number>
+ # grab-bootchart.sh uses $ANDROID_SERIAL.
$ANDROID_BUILD_TOP/system/core/init/grab-bootchart.sh
+One thing to watch for is that the bootchart will show init as if it started
+running at 0s. You'll have to look at dmesg to work out when the kernel
+actually started init.
+
Debugging init
--------------