Review follow-up:
- Warn once per (model, base_url) at the step-9 fallback via a module-level
dedup set (established _WARNED_* idiom). The fallback result is
deliberately never cached, so the un-deduped warning fired on every
resolution - e.g. once per gateway message via the session-hygiene path.
- Replace the three inline-mock pool-cleanup tests (which reproduced the
try/except block against a MagicMock and passed even with the production
code reverted) with a parametrized test that drives the real
BatchRunner.run() with a patched Pool; drop the CPython stdlib
signature change-detector test.
- Add a once-per-model warning regression test; clean up dead imports.
All tests verified to fail against pre-PR batch_runner.py/model_metadata.py
and pass with the fix (mutation check).
Salvage of #6629 by aaronlab (kshitijk4poor reworked against current main).
Three concerns from the original PR, reworked to address review feedback:
1. Context-length fallback diagnostic (agent/model_metadata.py):
get_model_context_length() silently returned 256K when all 9 detection
methods failed. Users with small-context models (8K, 32K) would get 256K
silently, causing hard-to-debug API context-length errors. Added a
warning log at the step 9 fallback with model name, base_url, and the
correct config override hint (model.context_length, not context_length).
The token-estimation ceiling-division fix from the original PR already
landed on main (5c2ecdec) with CJK handling — not duplicated here.
2. Fsync for batch trajectory writes (batch_runner.py):
Trajectory entries were written without flush/fsync, but the checkpoint
immediately marked them as completed. A crash between write and disk
sync would leave the checkpoint claiming completion with no trajectory
data on disk. Added flush() + os.fsync() before checkpoint update.
3. Pool cleanup on interruption (batch_runner.py):
Ctrl+C during pool.imap_unordered() relied on context manager cleanup
which can hang. Added explicit pool.terminate() + pool.join() for both
KeyboardInterrupt and Exception paths. The original PR used
pool.join(timeout=10) which is invalid — CPython's Pool.join() takes
no timeout parameter. Fixed to use pool.join() without arguments.
Tests:
- test_warning_emitted_on_fallback: verifies warning fires at step 9
- test_no_warning_when_cached: verifies no false warning when cache hits
- test_trajectory_entry_is_synced_to_disk: verifies os.fsync is called
- test_pool_terminate_called_on_exception: verifies cleanup on RuntimeError
- test_pool_terminate_called_on_keyboard_interrupt: verifies cleanup on Ctrl+C
- test_pool_join_called_without_timeout: verifies no timeout arg to join()
- test_real_pool_join_accepts_no_timeout: integration check on CPython API
Co-authored-by: Aaron Lab <aaronlab@users.noreply.github.com>
kshitijk4poor