risingwave_common_estimate_size/collections/
hashset.rs

1// Copyright 2025 RisingWave Labs
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15use std::collections::HashSet;
16use std::hash::Hash;
17
18use super::EstimatedVec;
19use crate::{EstimateSize, KvSize};
20
21#[derive(Default)]
22pub struct EstimatedHashSet<T: EstimateSize> {
23    inner: HashSet<T>,
24    heap_size: KvSize,
25}
26
27impl<T: EstimateSize> EstimateSize for EstimatedHashSet<T> {
28    fn estimated_heap_size(&self) -> usize {
29        // TODO: Add hashset internal size.
30        // https://github.com/risingwavelabs/risingwave/issues/9713
31        self.heap_size.size()
32    }
33}
34
35impl<T: EstimateSize> EstimatedHashSet<T>
36where
37    T: Eq + Hash,
38{
39    /// Insert into the cache.
40    pub fn insert(&mut self, value: T) -> bool {
41        let heap_size = self.heap_size.add_val(&value);
42        let inserted = self.inner.insert(value);
43        if inserted {
44            self.heap_size.set(heap_size);
45        }
46        inserted
47    }
48
49    /// Delete from the cache.
50    pub fn remove(&mut self, value: &T) -> bool {
51        let removed = self.inner.remove(value);
52        if removed {
53            self.heap_size.sub_val(value);
54        }
55        removed
56    }
57
58    /// Convert an [`EstimatedVec`] to a [`EstimatedHashSet`]. Do not need to recalculate the
59    /// heap size.
60    pub fn from_vec(v: EstimatedVec<T>) -> Self {
61        let heap_size = v.estimated_heap_size();
62        Self {
63            inner: HashSet::from_iter(v),
64            heap_size: KvSize::with_size(heap_size),
65        }
66    }
67}
68
69impl<T: EstimateSize> EstimatedHashSet<T> {
70    pub fn iter(&self) -> impl Iterator<Item = &T> {
71        self.inner.iter()
72    }
73}
risingwave_common_estimate_size/collections/hashset.rs

risingwave_common_estimate_size/collections/
hashset.rs
