* read path for new fst based index
* implement BlockAddrStoreWriter
* extract slop/derivation computation
* use better linear approximator and allow negative correction to approximator
* document format and reorder some fields
* optimize single block sstable size
* plug backward compat
* add fields_metadata to SegmentReader, add columnar docs
* use schema to resolve field, add test
* normalize paths
* merge for FieldsMetadata, add fields_metadata on Index
* Update src/core/segment_reader.rs
Co-authored-by: Paul Masurel <paul@quickwit.io>
* merge code paths
* add Hash
* move function oustide
---------
Co-authored-by: Paul Masurel <paul@quickwit.io>
* reduce number of allocations
Explanation makes up around 50% of all allocations (numbers not perf).
It's created during serialization but not called.
- Make Explanation optional in BM25
- Avoid allocations when using Explanation
* use Cow
In JSON Object field the presence of term frequencies depend on the
field.
Typically, a string with postiions indexed will have positions
while numbers won't.
The presence or absence of term freqs for a given term is unfortunately
encoded in a very passive way.
It is given by the presence of extra information in the skip info, or
the lack of term freqs after decoding vint blocks.
Before, after writing a segment, we would encode the segment correctly
(without any term freq for number in json object field).
However during merge, we would get the default term freq=1 value.
(this is default in the absence of encoded term freqs)
The merger would then proceed and attempt to decode 1 position when
there are in fact none.
This PR requires to explictly tell the posting serialize whether
term frequencies should be serialized for each new term.
Closes#2251
* docid deltas while indexing
storing deltas is especially helpful for repetitive data like logs.
In those cases, recording a doc on a term costed 4 bytes instead of 1
byte now.
HDFS Indexing 1.1GB Total memory consumption:
Before: 760 MB
Now: 590 MB
* use scan for delta decoding
* add support for delta-1 encoding posting list
* encode term frequency minus one
* don't emit tf for json integer terms
* make skipreader not pub(crate) mutable
* run coverage only after merge
coverage is a quite slow step in CI. It can be run only after merging
* Apply suggestions from code review
Co-authored-by: Paul Masurel <paul@quickwit.io>
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Co-authored-by: Paul Masurel <paul@quickwit.io>
* remove Document: DocumentDeserialize dependency
The dependency requires users to implement an API they may not use.
* remove unnecessary Document bounds
