1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
|
/**
* Copyright (C) 2018-present MongoDB, Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the Server Side Public License, version 1,
* as published by MongoDB, Inc.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* Server Side Public License for more details.
*
* You should have received a copy of the Server Side Public License
* along with this program. If not, see
* <http://www.mongodb.com/licensing/server-side-public-license>.
*
* As a special exception, the copyright holders give permission to link the
* code of portions of this program with the OpenSSL library under certain
* conditions as described in each individual source file and distribute
* linked combinations including the program with the OpenSSL library. You
* must comply with the Server Side Public License in all respects for
* all of the code used other than as permitted herein. If you modify file(s)
* with this exception, you may extend this exception to your version of the
* file(s), but you are not obligated to do so. If you do not wish to do so,
* delete this exception statement from your version. If you delete this
* exception statement from all source files in the program, then also delete
* it in the license file.
*/
#include "mongo/db/collection_index_usage_tracker.h"
#include <atomic>
#include "mongo/db/commands/server_status_metric.h"
#include "mongo/db/index/index_descriptor.h"
#include "mongo/util/assert_util.h"
#include "mongo/util/clock_source.h"
#define MONGO_LOGV2_DEFAULT_COMPONENT ::mongo::logv2::LogComponent::kStorage
namespace mongo {
namespace {
CounterMetric collectionScansCounter("queryExecutor.collectionScans.total");
CounterMetric collectionScansNonTailableCounter("queryExecutor.collectionScans.nonTailable");
} // namespace
CollectionIndexUsageTracker::CollectionIndexUsageTracker(
AggregatedIndexUsageTracker* aggregatedIndexUsageTracker, ClockSource* clockSource)
: _indexUsageStatsMap(std::make_shared<CollectionIndexUsageMap>()),
_clockSource(clockSource),
_aggregatedIndexUsageTracker(aggregatedIndexUsageTracker) {
invariant(_clockSource);
}
void CollectionIndexUsageTracker::recordIndexAccess(StringData indexName) {
invariant(!indexName.empty());
// The following update after fetching the map can race with the removal of this index entry
// from the map. However, that race is inconsequential and remains memory safe.
auto mapSharedPtr = atomic_load(&_indexUsageStatsMap);
auto it = mapSharedPtr->find(indexName);
if (it == mapSharedPtr->end()) {
// We are using an index that has been removed from the catalog, no need to track usage
return;
}
_aggregatedIndexUsageTracker->onAccess(it->second->features);
// Increment the index usage atomic counter.
it->second->accesses.fetchAndAdd(1);
}
void CollectionIndexUsageTracker::recordCollectionScans(unsigned long long collectionScans) {
_collectionScans.fetchAndAdd(collectionScans);
collectionScansCounter.increment(collectionScans);
}
void CollectionIndexUsageTracker::recordCollectionScansNonTailable(
unsigned long long collectionScansNonTailable) {
_collectionScansNonTailable.fetchAndAdd(collectionScansNonTailable);
collectionScansNonTailableCounter.increment(collectionScansNonTailable);
}
void CollectionIndexUsageTracker::registerIndex(StringData indexName,
const BSONObj& indexKey,
const IndexFeatures& features) {
invariant(!indexName.empty());
// Create a copy of the map to modify.
auto mapSharedPtr = atomic_load(&_indexUsageStatsMap);
auto mapCopy = std::make_shared<CollectionIndexUsageMap>(*mapSharedPtr);
dassert(mapCopy->find(indexName) == mapCopy->end());
// Create the map entry.
auto inserted = mapCopy->try_emplace(
indexName, make_intrusive<IndexUsageStats>(_clockSource->now(), indexKey, features));
invariant(inserted.second);
_aggregatedIndexUsageTracker->onRegister(inserted.first->second->features);
// Swap the modified map into place atomically.
atomic_store(&_indexUsageStatsMap, std::move(mapCopy));
}
void CollectionIndexUsageTracker::unregisterIndex(StringData indexName) {
invariant(!indexName.empty());
// Create a copy of the map to modify.
auto mapSharedPtr = atomic_load(&_indexUsageStatsMap);
auto mapCopy = std::make_shared<CollectionIndexUsageMap>(*mapSharedPtr);
auto it = mapCopy->find(indexName);
if (it != mapCopy->end()) {
_aggregatedIndexUsageTracker->onUnregister(it->second->features);
// Remove the map entry.
mapCopy->erase(it);
// Swap the modified map into place atomically.
atomic_store(&_indexUsageStatsMap, std::move(mapCopy));
}
}
std::shared_ptr<CollectionIndexUsageTracker::CollectionIndexUsageMap>
CollectionIndexUsageTracker::getUsageStats() const {
return atomic_load(&_indexUsageStatsMap);
}
CollectionIndexUsageTracker::CollectionScanStats
CollectionIndexUsageTracker::getCollectionScanStats() const {
return {_collectionScans.load(), _collectionScansNonTailable.load()};
}
} // namespace mongo
|
