fastfield_codecs
| Crates.io | fastfield_codecs |
| lib.rs | fastfield_codecs |
| version | 0.3.1 |
| source | src |
| created_at | 2021-08-26 00:00:04.81973 |
| updated_at | 2023-01-13 05:31:27.022722 |
| description | Fast field codecs used by tantivy |
| homepage | https://github.com/quickwit-oss/tantivy |
| repository | https://github.com/quickwit-oss/tantivy |
| max_upload_size | |
| id | 442401 |
| size | 164,540 |
(PSeitz)
documentation
https://docs.rs/fastfield_codecs/
README
Fast Field Codecs
This crate contains various fast field codecs, used to compress/decompress fast field data in tantivy.
Contributing
Contributing is pretty straightforward. Since the bitpacking is the simplest compressor, you can check it for reference.
A codec needs to implement 2 traits:
- A reader implementing
FastFieldCodecReaderto read the codec. - A serializer implementing
FastFieldCodecSerializerfor compression estimation and codec name + id.
Tests
Once the traits are implemented test and benchmark integration is pretty easy (see test_with_codec_data_sets and bench.rs).
Make sure to add the codec to the main.rs, which tests the compression ratio and estimation against different data sets. You can run it with:
cargo run --features bin
TODO
-
Add real world data sets in comparison
-
Add codec to cover sparse data sets
Codec Comparison
+----------------------------------+-------------------+------------------------+
| | Compression Ratio | Compression Estimation |
+----------------------------------+-------------------+------------------------+
| Autoincrement | | |
+----------------------------------+-------------------+------------------------+
| LinearInterpol | 0.000039572664 | 0.000004396963 |
+----------------------------------+-------------------+------------------------+
| MultiLinearInterpol | 0.1477348 | 0.17275847 |
+----------------------------------+-------------------+------------------------+
| Bitpacked | 0.28126493 | 0.28125 |
+----------------------------------+-------------------+------------------------+
| Monotonically increasing concave | | |
+----------------------------------+-------------------+------------------------+
| LinearInterpol | 0.25003937 | 0.26562938 |
+----------------------------------+-------------------+------------------------+
| MultiLinearInterpol | 0.190665 | 0.1883836 |
+----------------------------------+-------------------+------------------------+
| Bitpacked | 0.31251436 | 0.3125 |
+----------------------------------+-------------------+------------------------+
| Monotonically increasing convex | | |
+----------------------------------+-------------------+------------------------+
| LinearInterpol | 0.25003937 | 0.28125438 |
+----------------------------------+-------------------+------------------------+
| MultiLinearInterpol | 0.18676 | 0.2040086 |
+----------------------------------+-------------------+------------------------+
| Bitpacked | 0.31251436 | 0.3125 |
+----------------------------------+-------------------+------------------------+
| Almost monotonically increasing | | |
+----------------------------------+-------------------+------------------------+
| LinearInterpol | 0.14066513 | 0.1562544 |
+----------------------------------+-------------------+------------------------+
| MultiLinearInterpol | 0.16335973 | 0.17275847 |
+----------------------------------+-------------------+------------------------+
| Bitpacked | 0.28126493 | 0.28125 |
+----------------------------------+-------------------+------------------------+