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+ANRdaemon is a daemon to help analyze ANR due to CPU starvation by logging system
+activity when CPU usage is very high. The daemon uses debugfs underlying for
+logging. Trace are configured ahead by setting different modules in /d/tracing.
+Depending on the CPU usage level, the trace is turn on/off by writting to the
+global control /d/trace/trace_on. The raw trace file is stored at
+/d/tracing/trace.
+
+The daemon will be started at boot time and will be running with the following
+settings:
+$ ANRdaemon -t 9990 sched gfx am
+This means tracing will be enabled above 99.90% CPU utilization and will trace
+sched, gfx and am modules (See -h for more info).
+
+Use ANRdaemon_get_trace.sh [device serial] to dump and fetch the compressed trace file.
+
+The compressed trace file can be parsed using systrace:
+$ systrace.py --from-file=<path to compressed trace file>
+
+Known issue: in the systrace output, anrdaemon will show up when the trace is
+not running. This is because the daemon process turns off tracing when CPU usage
+drops, the last entry it leaves in the raw trace file is the scheduler switched
+from some other process to the daemon. Then sometime later (say 20 secs later),
+when the CPU usage becomes high and the daemon process turn on tracing again,
+the first entry in /d/tracing/trace logged by sched is switching away from the
+daemon process to some other process. Due to this artifact, when the raw trace
+file is parsed by systrace.py, the daemon process is shown as running for the
+whole 20secs (because from systrace's view, the two 20 sec apart sched trace
+entries regarding the daemon process indicates the daemon process ran continuously
+for all 20sec). However, this will not affect the actual captured trace during
+high CPU usage case.