adenzhou1350
e256b3c2cf
Follow-up on current main `7b3ba4c4` (merge commit `0b0475c1`): resolved the test import conflict, preserving both upstream imports and the original `warnings` import. The final PR diff is still limited to the same storage-option helper/call sites and regression class. AST comparisons preserve every upstream test definition and the original regression class/helper; both changed files compile and pass Ruff 0.15.1 check/format. Fresh locked-environment runtime validation was attempted with `uv run --locked --extra tests --extra dev pytest python/tests/test_namespace.py -q`, but dependency setup failed downloading the locked `pylance==14.0.0b12` wheel due a network connection error. No current-main native test result is claimed. Repository-wide Ruff reports 49 findings and 11 formatting differences in unchanged upstream docs/web-tests files; these were left outside this PR. CI approval and a human review are still pending. --- Original implementation and historical validation (before the main merge): Namespace-backed `create_table` accepts `data_storage_version` and `enable_v2_manifest_paths`, but neither sync nor async creation forwards them. The requested format/manifest settings are silently ignored. Normalize these deprecated arguments into the existing `new_table_*` storage options, matching ordinary connections. Explicit arguments take precedence; the caller's dictionary is not mutated. No Rust or native interface changes. Regression tests inspect persisted tables, including sync/async creation, populated/empty tables, stable/legacy formats, both manifest settings and explicit-option precedence. Validation on Linux/Python 3.12, based on current main `d3390a9`: - Rebuilt the exact-main native extension and reused that identical extension in separate baseline/candidate environments; only the candidate Python namespace wrapper differs. Dependencies came from the unchanged `uv.lock`. - Same complete `test_namespace.py`: baseline 16 regression failures and 39 passing controls; candidate **55 passed**, no skips/errors. - Ruff check/format and diff whitespace checks passed. This validates the local directory-namespace path, not a live Cloud service or the complete repository CI suite. Signed-off-by: Xucheng Zhou <aden1350@outlook.com>
LanceDB Python SDK
A Python library for LanceDB.
Installation
pip install lancedb
If no wheel is published for your platform, pip builds lancedb from the source distribution. That build needs a Rust toolchain and protoc (the Protocol Buffers compiler) on your PATH, and can take a while.
Pre-Haswell x86_64 hosts: lancedb-compat
The default lancedb wheel targets x86-64-haswell (AVX2 + FMA + F16C) for full performance on modern hardware. Pre-Haswell hosts — Intel Sandy Bridge / Ivy Bridge / Westmere; AMD Bulldozer / Piledriver / Steamroller — don't have AVX2 and crash with Illegal instruction at import lancedb.
For those hosts, install the lancedb-compat package instead:
pip install lancedb-compat
Same Python API (import lancedb works as usual). The compat wheel is compiled at the x86-64-v2 baseline (Nehalem-class) and uses runtime SIMD dispatch in the embedded lance crate to pick the right kernel tier (scalar / AVX / AVX+FMA / AVX2+FMA / AVX-512) at load time, so it still goes fast on modern hardware while running cleanly on the pre-Haswell silicon. Use lance.simd_info() from Python to verify which tier was selected.
lancedb and lancedb-compat install to the same lancedb/ namespace and conflict at install time. Pick one. To switch, pip uninstall lancedb first, then pip install lancedb-compat (or vice-versa).
If you need a custom baseline (or lancedb-compat isn't yet published for your platform), build from source with the override:
RUSTFLAGS="-C target-cpu=x86-64-v2" maturin build --release
pip install ./target/wheels/lancedb-*.whl
Preview Releases
Stable releases are created about every 2 weeks. For the latest features and bug fixes, you can install the preview release. These releases receive the same level of testing as stable releases, but are not guaranteed to be available for more than 6 months after they are released. Once your application is stable, we recommend switching to stable releases.
pip install --pre --extra-index-url https://pypi.fury.io/lancedb/ lancedb
Threading in CPU-limited containers
LanceDB uses separate pools for compute work and storage I/O. On a container with two visible CPUs, current releases intentionally use one compute worker by default; no manual configuration is needed. If every query logs an I/O core reservation warning on a two-CPU container, upgrade from LanceDB 0.21.1 or earlier.
The two commonly tuned environment variables control different resources:
LANCE_CPU_THREADSoverrides the number of compute workers. One worker is the appropriate setting for a two-CPU container when an explicit override is needed.LANCE_IO_THREADScontrols concurrent storage operations, not reserved CPU cores. Its default can be greater than the number of CPUs because I/O workers spend much of their time waiting for storage.
Keep the defaults unless measurements show that the workload benefits from an override. See the Lance threading model for the current defaults and tuning guidance.
Usage
Basic Example
import lancedb
db = lancedb.connect('<PATH_TO_LANCEDB_DATASET>')
table = db.open_table('my_table')
results = table.search([0.1, 0.3]).limit(20).to_list()
print(results)
Development
See CONTRIBUTING.md for information on how to contribute to LanceDB.