IssueTracker

Current state:

Baseline Profiles run a test sequence over and over looking at the profile after each iteration, it is "stable" if you get the same profile 3 iterations in a row.

https://github.com/androidx/androidx/blob/9c4774dd0d43a8bd9026ca1cc928c8c62629ecba/benchmark/benchmark-macro/src/main/java/androidx/benchmark/macro/BaselineProfiles.kt#L104

Given the profile is 10s of thousands of lines, matching 100% 3 times in a row might be difficult.

Feature request:

This is a feature request is to allow a custom merge policy to allow combining profiles dynamically.

Some possible policies:

• stop after 90% match is enough
• use the superset from 3 iterations
• uses the first repeated Profile, even if it wasn't in back to back iterations.
• iterate until I get an iteration that doesn't add any new rules to the superset of all previous iterations

API might look something like this:

interface Profile {
    fun profile(): Set<String>
}

interface ProfileMergePolicy {
    /**
     * Merge the latest profile into the previous profile.
     * 
     * @return true if we should do another iteration, false otherwise
     */
    fun merge(latestProfile: Profile): Boolean
    
    /**
     * After merge returns false, get the merged profile.
     */
    fun mergedProfile(): Profile
}