Avoid creating a MatchingWord for words that exceed the length limit

This commit is contained in:
Loïc Lecrenier 2022-11-24 09:00:53 +01:00
parent 86c34a996b
commit 8d0ace2d64
8 changed files with 111 additions and 62 deletions

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@ -70,6 +70,21 @@ pub type SmallVec8<T> = smallvec::SmallVec<[T; 8]>;
/// expressed in term of latitude and longitude.
pub type GeoPoint = rstar::primitives::GeomWithData<[f64; 3], (DocumentId, [f64; 2])>;
/// The maximum length a LMDB key can be.
///
/// Note that the actual allowed length is a little bit higher, but
/// we keep a margin of safety.
const MAX_LMDB_KEY_LENGTH: usize = 500;
/// The maximum length a field value can be when inserted in an LMDB key.
///
/// This number is determined by the keys of the different facet databases
/// and adding a margin of safety.
pub const MAX_FACET_VALUE_LENGTH: usize = MAX_LMDB_KEY_LENGTH - 20;
/// The maximum length a word can be
pub const MAX_WORD_LENGTH: usize = MAX_LMDB_KEY_LENGTH / 2;
pub const MAX_POSITION_PER_ATTRIBUTE: u32 = u16::MAX as u32 + 1;
// Convert an absolute word position into a relative position.

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@ -8,6 +8,7 @@ use charabia::Token;
use levenshtein_automata::{Distance, DFA};
use crate::search::build_dfa;
use crate::MAX_WORD_LENGTH;
type IsPrefix = bool;
@ -18,6 +19,17 @@ pub struct MatchingWords {
inner: Vec<(Vec<Rc<MatchingWord>>, Vec<PrimitiveWordId>)>,
}
impl fmt::Debug for MatchingWords {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
writeln!(f, "[")?;
for (matching_words, primitive_word_id) in self.inner.iter() {
writeln!(f, "({matching_words:?}, {primitive_word_id:?})")?;
}
writeln!(f, "]")?;
Ok(())
}
}
impl MatchingWords {
pub fn new(mut matching_words: Vec<(Vec<Rc<MatchingWord>>, Vec<PrimitiveWordId>)>) -> Self {
// Sort word by len in DESC order prioritizing the longuest matches,
@ -93,10 +105,13 @@ impl PartialEq for MatchingWord {
}
impl MatchingWord {
pub fn new(word: String, typo: u8, prefix: IsPrefix) -> Self {
pub fn new(word: String, typo: u8, prefix: IsPrefix) -> Option<Self> {
if word.len() > MAX_WORD_LENGTH {
return None;
}
let dfa = build_dfa(&word, typo, prefix);
Self { dfa, word, typo, prefix }
Some(Self { dfa, word, typo, prefix })
}
/// Returns the lenght in chars of the match in case of the token matches the term.
@ -335,9 +350,9 @@ mod tests {
#[test]
fn matching_words() {
let all = vec![
Rc::new(MatchingWord::new("split".to_string(), 1, true)),
Rc::new(MatchingWord::new("this".to_string(), 0, false)),
Rc::new(MatchingWord::new("world".to_string(), 1, true)),
Rc::new(MatchingWord::new("split".to_string(), 1, true).unwrap()),
Rc::new(MatchingWord::new("this".to_string(), 0, false).unwrap()),
Rc::new(MatchingWord::new("world".to_string(), 1, true).unwrap()),
];
let matching_words = vec![
(vec![all[0].clone()], vec![0]),

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@ -503,9 +503,9 @@ mod tests {
fn matching_words() -> MatchingWords {
let all = vec![
Rc::new(MatchingWord::new("split".to_string(), 0, false)),
Rc::new(MatchingWord::new("the".to_string(), 0, false)),
Rc::new(MatchingWord::new("world".to_string(), 1, true)),
Rc::new(MatchingWord::new("split".to_string(), 0, false).unwrap()),
Rc::new(MatchingWord::new("the".to_string(), 0, false).unwrap()),
Rc::new(MatchingWord::new("world".to_string(), 1, true).unwrap()),
];
let matching_words = vec![
(vec![all[0].clone()], vec![0]),
@ -595,8 +595,8 @@ mod tests {
#[test]
fn highlight_unicode() {
let all = vec![
Rc::new(MatchingWord::new("wessfali".to_string(), 1, true)),
Rc::new(MatchingWord::new("world".to_string(), 1, true)),
Rc::new(MatchingWord::new("wessfali".to_string(), 1, true).unwrap()),
Rc::new(MatchingWord::new("world".to_string(), 1, true).unwrap()),
];
let matching_words = vec![(vec![all[0].clone()], vec![0]), (vec![all[1].clone()], vec![1])];
@ -832,12 +832,12 @@ mod tests {
#[test]
fn partial_matches() {
let all = vec![
Rc::new(MatchingWord::new("the".to_string(), 0, false)),
Rc::new(MatchingWord::new("t".to_string(), 0, false)),
Rc::new(MatchingWord::new("he".to_string(), 0, false)),
Rc::new(MatchingWord::new("door".to_string(), 0, false)),
Rc::new(MatchingWord::new("do".to_string(), 0, false)),
Rc::new(MatchingWord::new("or".to_string(), 0, false)),
Rc::new(MatchingWord::new("the".to_string(), 0, false).unwrap()),
Rc::new(MatchingWord::new("t".to_string(), 0, false).unwrap()),
Rc::new(MatchingWord::new("he".to_string(), 0, false).unwrap()),
Rc::new(MatchingWord::new("door".to_string(), 0, false).unwrap()),
Rc::new(MatchingWord::new("do".to_string(), 0, false).unwrap()),
Rc::new(MatchingWord::new("or".to_string(), 0, false).unwrap()),
];
let matching_words = vec![
(vec![all[0].clone()], vec![0]),

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@ -550,21 +550,20 @@ struct MatchingWordCache {
map: HashMap<(String, u8, bool), Rc<MatchingWord>>,
}
impl MatchingWordCache {
fn insert(&mut self, word: String, typo: u8, prefix: bool) -> Rc<MatchingWord> {
// Toggle the (un)commented code to switch between cached and non-cached
// implementations.
// self.all.push(MatchingWord::new(word, typo, prefix));
// self.all.len() - 1
fn insert(&mut self, word: String, typo: u8, prefix: bool) -> Option<Rc<MatchingWord>> {
match self.map.entry((word.clone(), typo, prefix)) {
Entry::Occupied(idx) => idx.get().clone(),
Entry::Occupied(idx) => Some(idx.get().clone()),
Entry::Vacant(vacant) => {
let matching_word = Rc::new(MatchingWord::new(word, typo, prefix));
let matching_word = Rc::new(MatchingWord::new(word, typo, prefix)?);
self.all.push(matching_word.clone());
vacant.insert(matching_word.clone());
matching_word
Some(matching_word)
}
}
// To deactivate the cache, for testing purposes, use the following instead:
// let matching_word = Rc::new(MatchingWord::new(word, typo, prefix)?);
// self.all.push(matching_word.clone());
// Some(matching_word)
}
}
@ -591,17 +590,20 @@ fn create_matching_words(
for synonym in synonyms {
let synonym = synonym
.into_iter()
.map(|syn| matching_word_cache.insert(syn, 0, false))
.flat_map(|syn| matching_word_cache.insert(syn, 0, false))
.collect();
matching_words.push((synonym, vec![id]));
}
}
if let Some((left, right)) = split_best_frequency(ctx, &word)? {
let left = matching_word_cache.insert(left.to_string(), 0, false);
let right = matching_word_cache.insert(right.to_string(), 0, false);
if let Some(left) = matching_word_cache.insert(left.to_string(), 0, false) {
if let Some(right) = matching_word_cache.insert(right.to_string(), 0, false)
{
matching_words.push((vec![left, right], vec![id]));
}
}
}
let (word_len_one_typo, word_len_two_typo) = ctx.min_word_len_for_typo()?;
let exact_words = ctx.exact_words();
@ -614,8 +616,10 @@ fn create_matching_words(
matching_word_cache.insert(word, typo, prefix)
}
};
if let Some(matching_word) = matching_word {
matching_words.push((vec![matching_word], vec![id]));
}
}
// create a CONSECUTIVE matchings words wrapping all word in the phrase
PrimitiveQueryPart::Phrase(words) => {
let ids: Vec<_> =
@ -623,7 +627,7 @@ fn create_matching_words(
let words = words
.into_iter()
.flatten()
.map(|w| matching_word_cache.insert(w, 0, false))
.flat_map(|w| matching_word_cache.insert(w, 0, false))
.collect();
matching_words.push((words, ids));
}
@ -681,7 +685,7 @@ fn create_matching_words(
for synonym in synonyms {
let synonym = synonym
.into_iter()
.map(|syn| matching_word_cache.insert(syn, 0, false))
.flat_map(|syn| matching_word_cache.insert(syn, 0, false))
.collect();
matching_words.push((synonym, ids.clone()));
}
@ -704,9 +708,11 @@ fn create_matching_words(
matching_word_cache.insert(word, typo, is_prefix)
}
};
if let Some(matching_word) = matching_word {
matching_words.push((vec![matching_word], ids));
}
}
}
if !is_last {
ngrams(
@ -1341,6 +1347,27 @@ mod test {
);
}
#[test]
fn test_dont_create_matching_word_for_long_words() {
let index = TempIndex::new();
let rtxn = index.read_txn().unwrap();
let query = "what a supercalifragilisticexpialidocioussupercalifragilisticexpialidocioussupercalifragilisticexpialidocioussupercalifragilisticexpialidocioussupercalifragilisticexpialidocioussupercalifragilisticexpialidocioussupercalifragilisticexpialidocioussupercalifragilisticexpialidocious house";
let mut builder = QueryTreeBuilder::new(&rtxn, &index).unwrap();
builder.words_limit(10);
let (_, _, matching_words) = builder.build(query.tokenize()).unwrap().unwrap();
insta::assert_snapshot!(format!("{matching_words:?}"), @r###"
[
([MatchingWord { word: "house", typo: 1, prefix: true }], [3])
([MatchingWord { word: "house", typo: 1, prefix: true }], [2])
([MatchingWord { word: "whata", typo: 1, prefix: false }], [0, 1])
([MatchingWord { word: "house", typo: 1, prefix: true }], [2])
([MatchingWord { word: "house", typo: 1, prefix: true }], [1])
([MatchingWord { word: "what", typo: 0, prefix: false }], [0])
([MatchingWord { word: "a", typo: 0, prefix: false }], [1])
]
"###);
}
#[test]
fn disable_typo_on_word() {
let query = "goodbye";
@ -1380,9 +1407,8 @@ mod test {
}
}
// This test must be run
#[test]
fn ten_words() {
fn memory_usage_of_ten_word_query() {
let resident_before = ALLOC.resident.load(atomic::Ordering::SeqCst);
let allocated_before = ALLOC.allocated.load(atomic::Ordering::SeqCst);
@ -1395,12 +1421,20 @@ mod test {
let resident_after = ALLOC.resident.load(atomic::Ordering::SeqCst);
let allocated_after = ALLOC.allocated.load(atomic::Ordering::SeqCst);
insta::assert_snapshot!(format!("{}", resident_after - resident_before), @"4521710");
insta::assert_snapshot!(format!("{}", allocated_after - allocated_before), @"7259092");
// Weak check on the memory usage
// Don't keep more than 5MB. (Arguably 5MB is already too high)
assert!(resident_after - resident_before < 5_000_000);
// Don't allocate more than 10MB.
assert!(allocated_after - allocated_before < 10_000_000);
// Note, if the matching word cache is deactivated, the memory usage is:
// insta::assert_snapshot!(format!("{}", resident_after - resident_before), @"91311265");
// insta::assert_snapshot!(format!("{}", allocated_after - allocated_before), @"125948410");
// Use these snapshots to measure the exact memory usage.
// The values below were correct at the time I wrote them.
// insta::assert_snapshot!(format!("{}", resident_after - resident_before), @"4486950");
// insta::assert_snapshot!(format!("{}", allocated_after - allocated_before), @"7107502");
// Note, with the matching word cache deactivated, the memory usage was:
// insta::assert_snapshot!(format!("{}", resident_after - resident_before), @"91248697");
// insta::assert_snapshot!(format!("{}", allocated_after - allocated_before), @"125697588");
// or about 20x more resident memory (90MB vs 4.5MB)
// Use x

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@ -7,11 +7,11 @@ use charabia::{SeparatorKind, Token, TokenKind, TokenizerBuilder};
use roaring::RoaringBitmap;
use serde_json::Value;
use super::helpers::{
concat_u32s_array, create_sorter, sorter_into_reader, GrenadParameters, MAX_WORD_LENGTH,
};
use super::helpers::{concat_u32s_array, create_sorter, sorter_into_reader, GrenadParameters};
use crate::error::{InternalError, SerializationError};
use crate::{absolute_from_relative_position, FieldId, Result, MAX_POSITION_PER_ATTRIBUTE};
use crate::{
absolute_from_relative_position, FieldId, Result, MAX_POSITION_PER_ATTRIBUTE, MAX_WORD_LENGTH,
};
/// Extracts the word and positions where this word appear and
/// prefixes it by the document id.

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@ -6,9 +6,8 @@ use heed::BytesEncode;
use super::helpers::{create_sorter, sorter_into_reader, try_split_array_at, GrenadParameters};
use crate::heed_codec::facet::{FacetGroupKey, FacetGroupKeyCodec};
use crate::heed_codec::StrRefCodec;
use crate::update::index_documents::helpers::MAX_FACET_VALUE_LENGTH;
use crate::update::index_documents::merge_cbo_roaring_bitmaps;
use crate::{FieldId, Result};
use crate::{FieldId, Result, MAX_FACET_VALUE_LENGTH};
/// Extracts the facet string and the documents ids where this facet string appear.
///

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@ -12,9 +12,8 @@ use serde_json::Value;
use super::helpers::{create_sorter, keep_first, sorter_into_reader, GrenadParameters};
use crate::error::InternalError;
use crate::facet::value_encoding::f64_into_bytes;
use crate::update::index_documents::helpers::MAX_FACET_VALUE_LENGTH;
use crate::update::index_documents::{create_writer, writer_into_reader};
use crate::{CboRoaringBitmapCodec, DocumentId, FieldId, Result, BEU32};
use crate::{CboRoaringBitmapCodec, DocumentId, FieldId, Result, BEU32, MAX_FACET_VALUE_LENGTH};
/// Extracts the facet values of each faceted field of each document.
///

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@ -18,20 +18,7 @@ pub use merge_functions::{
serialize_roaring_bitmap, MergeFn,
};
/// The maximum length a LMDB key can be.
///
/// Note that the actual allowed length is a little bit higher, but
/// we keep a margin of safety.
const MAX_LMDB_KEY_LENGTH: usize = 500;
/// The maximum length a field value can be when inserted in an LMDB key.
///
/// This number is determined by the keys of the different facet databases
/// and adding a margin of safety.
pub const MAX_FACET_VALUE_LENGTH: usize = MAX_LMDB_KEY_LENGTH - 20;
/// The maximum length a word can be
pub const MAX_WORD_LENGTH: usize = MAX_LMDB_KEY_LENGTH / 2;
use crate::MAX_WORD_LENGTH;
pub fn valid_lmdb_key(key: impl AsRef<[u8]>) -> bool {
key.as_ref().len() <= MAX_WORD_LENGTH * 2 && !key.as_ref().is_empty()