This PR includes / depends on #25709
The two concepts of Syncer and SyncClient are confusing, as is the current API for passing custom sync functions.
This PR refactors Tune's syncing behavior. The Sync client concept is hard deprecated. Instead, we offer a well defined Syncer API that can be extended to provide own syncing functionality. However, the default will be to use Ray AIRs file transfer utilities.
New API:
- Users can pass `syncer=CustomSyncer` which implements the `Syncer` API
- Otherwise our off-the-shelf syncing is used
- As before, syncing to cloud disables syncing to driver
Changes:
- Sync client is removed
- Syncer interface introduced
- _DefaultSyncer is a wrapper around the URI upload/download API from Ray AIR
- SyncerCallback only uses remote tasks to synchronize data
- Rsync syncing is fully depracated and removed
- Docker and kubernetes-specific syncing is fully deprecated and removed
- Testing is improved to use `file://` URIs instead of mock sync clients
Currently, team:ml spans all ML (Tune, Train, AIR) tests and rllib tests. rllib tests are much more flaky and it would be good to split them up in the flaky test tracker. This PR changes Rllib-tests from team:ml to team:rllib to enable this separation.
Co-authored-by: Antoni Baum <antoni.baum@protonmail.com>
**Update**: This PR is now part 3 of a three PR group to consolidate the checkpoints.
1. Part 1 adds the common checkpoint management class #24771
2. Part 2 adds the integration for Ray Train #24772
3. This PR builds on #24772 and includes all changes. It moves the Ray Tune integration to use the new common checkpoint manager class.
Old PR description:
This PR consolidates the Ray Train and Tune checkpoint managers. These concepts previously did something very similar but in different modules. To simplify maintenance in the future, we've consolidated the common core.
- This PR keeps full compatibility with the previous interfaces and implementations. This means that for now, Train and Tune will have separate CheckpointManagers that both extend the common core
- This PR prepares Tune to move to a CheckpointStrategy object
- In follow-up PRs, we can further unify interfacing with the common core, possibly removing any train- or tune-specific adjustments (e.g. moving to setup on init rather on runtime for Ray Train)
Co-authored-by: Antoni Baum <antoni.baum@protonmail.com>
Bazel operates by simply running the python scripts given to it in `py_test`. If the script doesn't invoke pytest on itself in the `if _name__ == "__main__"` snippet, no tests will be ran, and the script will pass. This has led to several tests (indeed, some are fixed in this PR) that, despite having been written, have never ran in CI. This PR adds a lint check to check all `py_test` sources for the presence of `if _name__ == "__main__"` snippet, and will fail CI if there are any detected without it. This system is only enabled for libraries right now (tune, train, air, rllib), but it could be trivially extended to other modules if approved.
