2052251 - Investigate and improve performace of mach lint for Android

Status: ASSIGNED

(Firefox for Android :: Tooling, enhancement)

Description

[Aaditya Dhingra [:adhingra]]

Currently AGP lint takes 15+ minutes to run locally and similar on taskcluster. After some invetigation, most of the time (10+ minutes) goes in the actual lintDebug task, even when all other tasks are UP-TO-DATE. Using https://github.com/google/android-lint-performance-probe, the report generated shows that again most of the time goes in LintDriver task (1194589 ms) with next task taking (23083 ms).

The LintDriver is the engine that drives the entire linting process. Before the individual detectors can look for errors, the LintDriver has to parse all your Java/Kotlin code into a Universal Abstract Syntax Tree (UAST) and perform full type resolution. Because of how the Android Lint tool is architected, all of this heavy lifting (parsing, indexing, and type resolution) is logged under LintDriver. The individual detectors just traverse the already-built UAST.

To start-off, we can make it so fenix-linter doesn't run the lint tasks on components. When running mach lint, we already ignore the reports generated by AC lint tasks, but still run the gradle tasks. Skipping AC lint tasks in fenix linter brings the time down to 7 minutes locally. the same change saves about 3+ minutes on taskcluster. Taskcluster will still run all linters, including AC lints and locally we can still run mach lint -l android-ac linter as they normally would to catch lint issues in AC

Comment 1

[Aaditya Dhingra [:adhingra]]

Attachment: Bug 2052251 - Don't run AC lint when linting fenix/focus.

When running fenix lint, we already ignore the reports generated by AC lint tasks, but still run the AC lint gradle tasks. Skipping AC lint tasks in fenix linter brings the time down to 7 minutes locally. the same change saves about 3+ minutes on taskcluster. Taskcluster will still run all linters, including AC lints and locally we can still run mach lint -l android-ac linter as we normally would to catch lint issues in AC

before: https://scans.gradle.com/s/pi7nzxvjlpyxc
with change: https://scans.gradle.com/s/7h5w4m3ug47gc

Comment 2

[Aaditya Dhingra [:adhingra]]

Attachment: Bug 2052251 - Add gradle flag for linter to identify which files modified locally. r=ahochheiden,nalexander

Comment 3

[Aaditya Dhingra [:adhingra]]

Attachment: Bug 2052251 - Only run linter on components that were modified instead of all android-components locally. r=ahochheiden,nalexander

Comment 4

[Aaditya Dhingra [:adhingra]]

Attachment: Bug 2052251 - Only have one android linter and let it decide what tasks to run - single gradle invocation. r=ahochheiden,nalexander

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/1634967ede3c
https://hg.mozilla.org/integration/autoland/rev/aa152450ec10
Don't run AC lint when linting fenix/focus. r=geckoview-reviewers,nalexander,ahochheiden

Comment 6

[Cosmin Sabou [:CosminS]]

https://hg.mozilla.org/mozilla-central/rev/aa152450ec10