使用atrace抓取systrace log

/system/etc/init/atrace.rc /system/bin/atrace
mount debugfs
atrace --list
/sys/kernel/debug/tracing

1：抓取atrace之前需要根据内存大小修改trace buffer size
adb shell "echo 20960 > /sys/kernel/debug/tracing/buffer_size_kb"
Recommends values:
For 1G ram device: 4096
For 2G ram device: 10960
For 4G and above ram device: 20960

2：run atrace background
adb shell
atrace -z -b 20960 -t 12 gfx input audio view webview wm am hal app res dalvik rs bionic
power sched freq idle load sync workq memreclaim > /data/local/tmp/atrace.out &

3：run atrace async mode
Connect USB
adb shell atrace --async_start -z -b 20960 gfx input audio view webview wm am hal app res
dalvik rs bionic power sched freq idle load sync workq memreclaim
Unplug USB and reproduce your issue
Once issue get replicated, plugin USB immediately and run
adb shell atrace --async_dump -z -b 20960 gfx input audio view webview wm am hal app res dalvik
rs bionic power sched freq idle load sync workq memreclaim >atrace.out

4：解析atrace
python systrace.py --from-file 31off_atrace.out -o 31off_atrace.html

5：配置内核模块trace events后，抓取atrace
大多数内核模块都有trace配置，我们只需要开启 其trace event。

adb root
adb shell "echo > /d/tracing/set_event"
adb shell "echo 0 > /sys/kernel/debug/tracing/tracing_on"
adb shell "echo > /sys/kernel/debug/tracing/trace"
adb shell "echo 20960 > /sys/kernel/debug/tracing/buffer_size_kb"

adb shell "echo 1 > /proc/sys/kernel/sched_schedstats"
adb shell "echo 1 > /sys/kernel/debug/tracing/events/sched/enable"
adb shell "echo 1 > /sys/kernel/debug/tracing/events/f2fs/enable"

adb shell "echo sched:*>> /sys/kernel/debug/tracing/set_event"
adb shell "echo f2fs:*>> /sys/kernel/debug/tracing/set_event"

adb shell "echo 512 > /sys/kernel/debug/tracing/saved_cmdlines_size"

adb shell "echo 1 > /sys/kernel/debug/tracing/events/workqueue/enable"
adb shell "echo 1 > /sys/kernel/debug/tracing/options/record-tgid"

adb shell atrace -b 41920 -t 15 -z gfx irq input view webview wm am hal res rs bionic power sched freq idle disk pm dalvik network > C:UsersaiboDesktoplog31off_atrace.out