1# Android Version Notes 2This page documents all the caveats of using Perfetto on older versions of 3Android. Because of the yearly release cycle, it's often the case that a 4feature is shipped but we later discover a bug/problem which makes the feature 5not usable or needs to be used in a very specific way. 6 7## U- 8### New features 9* The CLONE_SNAPSHOT trigger mode was introduced. 10* String field filtering in traces was introduced. 11 12### Caveats 13* On the CLONE_SNAPSHOT codepath, the trace UUID gets rewritten when the session 14 is clone but a statsd atom linking the two is not emitted. This means we 15 should be careful to exclude any "clone-only" sessions as being "failed" 16 sessions. 17 18## T- 19### New features 20* Reporting traces through the framework was introduced. 21 22### Caveats 23* CLONE_SNAPSHOT does not exist in T- but there is a subtle edge case 24 (b/274931668) which means it's quite dangerous to specify CLONE_SNAPSHOT on 25 configs being sent to T- devices. 26 27## P 28### New features 29* Perfetto was included in the system image! 30 31### Caveats 32* --txt option is not supported so configs must be binary encoded. 33