milvus/internal/core/src/common/RangeSearchHelper.cpp
Cai Yudong a0a4ec8b67
enhance: make range search param check message more meaningful (#32006)
Issue: #31970

Signed-off-by: Cai Yudong <yudong.cai@zilliz.com>
2024-04-09 16:17:26 +08:00

139 lines
4.9 KiB
C++

// Copyright (C) 2019-2020 Zilliz. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance
// with the License. You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software distributed under the License
// is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
// or implied. See the License for the specific language governing permissions and limitations under the License
#include <queue>
#include <vector>
#include <functional>
#include "common/Utils.h"
#include "common/RangeSearchHelper.h"
namespace milvus {
namespace {
using ResultPair = std::pair<float, int64_t>;
}
/* Sort and return TOPK items as final range search result */
DatasetPtr
ReGenRangeSearchResult(DatasetPtr data_set,
int64_t topk,
int64_t nq,
const std::string& metric_type) {
/**
* nq: number of queries;
* lims: the size of lims is nq + 1, lims[i+1] - lims[i] refers to the size of RangeSearch result queries[i]
* for example, the nq is 5. In the selected range,
* the size of RangeSearch result for each nq is [1, 2, 3, 4, 5],
* the lims will be [0, 1, 3, 6, 10, 15];
* ids: the size of ids is lim[nq],
* {
* i(0,0), i(0,1), …, i(0,k0-1),
* i(1,0), i(1,1), …, i(1,k1-1),
* ... ...
* i(n-1,0), i(n-1,1), …, i(n-1,kn-1)
* }
* i(0,0), i(0,1), …, i(0,k0-1) means the ids of RangeSearch result queries[0], k0 equals lim[1] - lim[0];
* dist: the size of ids is lim[nq],
* {
* d(0,0), d(0,1), …, d(0,k0-1),
* d(1,0), d(1,1), …, d(1,k1-1),
* ... ...
* d(n-1,0), d(n-1,1), …, d(n-1,kn-1)
* }
* d(0,0), d(0,1), …, d(0,k0-1) means the distances of RangeSearch result queries[0], k0 equals lim[1] - lim[0];
*/
auto lims = GetDatasetLims(data_set);
auto id = GetDatasetIDs(data_set);
auto dist = GetDatasetDistance(data_set);
// use p_id and p_dist to GenResultDataset after sorted
auto p_id = new int64_t[topk * nq];
auto p_dist = new float[topk * nq];
std::fill_n(p_id, topk * nq, -1);
std::fill_n(p_dist, topk * nq, std::numeric_limits<float>::max());
/*
* get result for one nq
* IP: 1.0 range_filter radius
* |------------+---------------| min_heap descending_order
* |___ ___|
* V
* topk
*
* L2: 0.0 range_filter radius
* |------------+---------------| max_heap ascending_order
* |___ ___|
* V
* topk
*/
std::function<bool(const ResultPair&, const ResultPair&)> cmp =
std::less<>();
if (PositivelyRelated(metric_type)) {
cmp = std::greater<>();
}
// The subscript of p_id and p_dist
for (int i = 0; i < nq; i++) {
std::priority_queue<ResultPair, std::vector<ResultPair>, decltype(cmp)>
pq(cmp);
auto capacity = std::min<int64_t>(lims[i + 1] - lims[i], topk);
for (size_t j = lims[i]; j < lims[i + 1]; j++) {
auto curr = ResultPair(dist[j], id[j]);
if (pq.size() < capacity) {
pq.push(curr);
} else if (cmp(curr, pq.top())) {
pq.pop();
pq.push(curr);
}
}
for (int j = capacity - 1; j >= 0; j--) {
auto& node = pq.top();
p_dist[i * topk + j] = node.first;
p_id[i * topk + j] = node.second;
pq.pop();
}
}
return GenResultDataset(nq, topk, p_id, p_dist);
}
void
CheckRangeSearchParam(float radius,
float range_filter,
const std::string& metric_type) {
/*
* IP: 1.0 range_filter radius
* |------------+---------------| range_filter > radius
* L2: 0.0 range_filter radius
* |------------+---------------| range_filter < radius
*
*/
if (PositivelyRelated(metric_type)) {
AssertInfo(range_filter > radius,
"metric type ({}), range_filter({}) must be greater than "
"radius({})",
metric_type.c_str(),
range_filter,
radius);
} else {
AssertInfo(range_filter < radius,
"metric type ({}), range_filter({}) must be less than "
"radius({})",
metric_type.c_str(),
range_filter,
radius);
}
}
} // namespace milvus