profcollectd: compress ETM data instead of decoding it when recording
To compare the cpu-cycles and disk cost of recording ETM data:
Storing raw ETM data takes 2.9 * 10^9 cpu-cycles and 107M storage.
Storing compressed ETM data takes 3.5 *10^9 cpu-cycles and 20M storage.
Storing decoded ETM data takes 6.7 * 10^9 cpu-cycles and 1M storage.
The default storage limit is 768M, which can store about 40 compressed
profiles. If a profile is generated every 10min, this can cover 7 hours
recording.
So switch to compressing ETM data to reduce cpu-cycles and power cost.
Bug: 343557442
Test: run profcollectd
Change-Id: Idcd6eea5e3901b5b2df5e00471824bb129971aa9
1 file changed