fix(asap-query-engine): unblock hard_cap_back_pressure hang in lib tests - #145
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…_until_flusher_drains hang in lib tests The lib-test binary deadlocked on `tests::persistence_integration_tests::hard_cap_back_pressure_blocks_inserts_until_flusher_drains` because the persistence flusher's `EpochSource::snapshot_sealed_epoch` stub on `SimpleMapStorePerKey` (legacy-expr refactor) was a `panic!`, not the no-op the comment described. The panic killed the `simple-map-store-flusher` thread on the first tick that had anything to flush; subsequent over-cap inserts then sat in `wait_for_memory_under` for the full 30 s `INSERT_BACK_PRESSURE_TIMEOUT` each (200 inserts × 30 s ≈ 100 min of futex_wait at 0 % CPU — exactly the reported symptom). Two minimal changes: * Replace the `panic!` in `EpochSource::snapshot_sealed_epoch` with `Ok(None)` (the same shape the flusher already uses for the already-evicted race). The flusher now skips epochs instead of dying; sealed memory stays in-process until the SketchIndex-backed snapshot path lands, but inserts make forward progress. * Replace the matching `panic!` in `Store::query_disk_parts` with the `Ok(())` its own comment said it should be (no disk parts read until the deserialize path is rebuilt). The three persistence-integration tests that require the flusher to actually drain are `#[ignore]`'d with a pointer to this refactor: `with_persistence_flushes_sealed_epochs_to_disk`, `query_read_through_merges_memory_and_disk_ranges`, and the original hanger `hard_cap_back_pressure_blocks_inserts_until_flusher_drains`. The fourth test in that file (`construct_and_drop_shuts_flusher_cleanly`) still runs — it never triggers the snapshot path. After this change `cargo test --release -p query_engine_rust --lib` completes the test binary in ~1.2 s (807 pass, 7 ignored). Two pre-existing `schema_timeline_dispatch_tests` failures remain — they also reproduce on plain `origin/main` and are out of scope for this hang fix. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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… removed datafusion serde (#146) PR #145 silenced a real futex deadlock by stubbing `EpochSource::snapshot_sealed_epoch` and `Store::query_disk_parts` to no-ops, and `#[ignore]`'d three persistence-integration tests that exercised the disk flush + read-back path: - `with_persistence_flushes_sealed_epochs_to_disk` - `query_read_through_merges_memory_and_disk_ranges` - `hard_cap_back_pressure_blocks_inserts_until_flusher_drains` The disk path those tests exercise was built on the datafusion-backed `accumulator_serde` SerDe that PR #123 removed. Rather than rebuild that SerDe for a SimpleMapStore variant that is itself slated for replacement by SketchIndex-backed persistence, the three tests are retired here. The remaining `construct_and_drop_shuts_flusher_cleanly` test stays — it only exercises the flusher's lifecycle, not the SerDe path. Test count: 807 passed (unchanged), 4 ignored (was 7). Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Summary
cargo test --release -p query_engine_rust --libwas hanging indefinitely (14+ min at 0 % CPU, two threads infutex_wait_queue_me). Bisected totests::persistence_integration_tests::hard_cap_back_pressure_blocks_inserts_until_flusher_drains.EpochSource::snapshot_sealed_epoch(and its siblingStore::query_disk_parts) onSimpleMapStorePerKeyaspanic!stubs even though their TODO comments described a safeOk(None)/Ok(())no-op. The first flusher tick that had a sealed epoch to snapshot panicked, killing thesimple-map-store-flusherthread; every subsequent over-cap insert then waited the full 30 sINSERT_BACK_PRESSURE_TIMEOUTinwait_for_memory_under(200 inserts × 30 s ≈ 100 minutes — the observed hang).#[ignore]the three persistence-integration tests that require an actually-draining flusher (with a comment pointing at the SketchIndex-backed refactor that needs to land before re-enabling).construct_and_drop_shuts_flusher_cleanlystays enabled — it never exercises the snapshot path.Result
cargo test --release -p query_engine_rust --libnow finishes the test binary in ~1.2 s. 807 pass, 7 ignored (4 pre-existing perf tests + the 3 newly-ignored persistence integration tests). Twoschema_timeline_dispatch_testsfailures remain — verified pre-existing on plainorigin/mainand unrelated to this hang.Test plan
cargo test --release -p query_engine_rust --libcompletes (no deadlock).tests::persistence_integration_tests::construct_and_drop_shuts_flusher_cleanlystill passes (flusher start/shutdown not broken).flusher::tests::*unit tests pass (the in-treeFakeSourcecontinues to provide real snapshots, so the flusher's happy path is still exercised).snapshot_sealed_epoch/query_disk_partslands, remove the#[ignore]attributes on the three persistence integration tests.