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
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
|
/**
* Copyright (C) 2020-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.
*/
#pragma once
#include "mongo/db/repl/primary_only_service.h"
#include "mongo/db/s/resharding/recipient_document_gen.h"
#include "mongo/db/s/resharding/resharding_oplog_applier.h"
#include "mongo/db/s/resharding/resharding_oplog_fetcher.h"
#include "mongo/s/resharding/type_collection_fields_gen.h"
#include "mongo/util/concurrency/thread_pool.h"
namespace mongo {
class ReshardingCollectionCloner;
class ReshardingTxnCloner;
namespace resharding {
/**
* Creates the temporary resharding collection locally by loading the collection options and
* collection indexes from the original collection's primary and MinKey owning chunk shards,
* respectively.
*/
void createTemporaryReshardingCollectionLocally(OperationContext* opCtx,
const NamespaceString& originalNss,
const NamespaceString& reshardingNss,
const UUID& reshardingUUID,
const UUID& existingUUID,
Timestamp fetchTimestamp);
std::vector<NamespaceString> ensureStashCollectionsExist(
OperationContext* opCtx,
const ChunkManager& cm,
const UUID& existingUUID,
std::vector<DonorShardMirroringEntry> donorShards);
} // namespace resharding
class ReshardingRecipientService final : public repl::PrimaryOnlyService {
public:
static constexpr StringData kServiceName = "ReshardingRecipientService"_sd;
explicit ReshardingRecipientService(ServiceContext* serviceContext)
: PrimaryOnlyService(serviceContext) {}
~ReshardingRecipientService() = default;
class RecipientStateMachine;
StringData getServiceName() const override {
return kServiceName;
}
NamespaceString getStateDocumentsNS() const override {
return NamespaceString::kRecipientReshardingOperationsNamespace;
}
ThreadPool::Limits getThreadPoolLimits() const override {
// TODO Limit the size of ReshardingRecipientService thread pool.
return ThreadPool::Limits();
}
std::shared_ptr<PrimaryOnlyService::Instance> constructInstance(
BSONObj initialState) const override;
};
/**
* Represents the current state of a resharding recipient operation on this shard. This class
* drives state transitions and updates to underlying on-disk metadata.
*/
class ReshardingRecipientService::RecipientStateMachine final
: public repl::PrimaryOnlyService::TypedInstance<RecipientStateMachine> {
public:
explicit RecipientStateMachine(const BSONObj& recipientDoc);
~RecipientStateMachine();
SemiFuture<void> run(std::shared_ptr<executor::ScopedTaskExecutor> executor,
const CancelationToken& token) noexcept override;
void interrupt(Status status) override;
/**
* Returns a Future that will be resolved when all work associated with this Instance has
* completed running.
*/
SharedSemiFuture<void> getCompletionFuture() const {
return _completionPromise.getFuture();
}
boost::optional<BSONObj> reportForCurrentOp(
MongoProcessInterface::CurrentOpConnectionsMode,
MongoProcessInterface::CurrentOpSessionsMode) noexcept override;
void onReshardingFieldsChanges(const TypeCollectionReshardingFields& reshardingFields);
private:
// The following functions correspond to the actions to take at a particular recipient state.
void _transitionToCreatingTemporaryReshardingCollection();
void _createTemporaryReshardingCollectionThenTransitionToCloning();
ExecutorFuture<void> _cloneThenTransitionToApplying(
const std::shared_ptr<executor::ScopedTaskExecutor>& executor,
const CancelationToken& cancelToken);
void _applyThenTransitionToSteadyState();
ExecutorFuture<void> _awaitAllDonorsMirroringThenTransitionToStrictConsistency(
const std::shared_ptr<executor::ScopedTaskExecutor>& executor);
ExecutorFuture<void> __awaitCoordinatorHasDecisionPersistedThenTransitionToRenaming(
const std::shared_ptr<executor::ScopedTaskExecutor>& executor);
void _renameTemporaryReshardingCollection();
void _fulfillAllDonorsPreparedToDonate(Timestamp);
// Transitions the state on-disk and in-memory to 'endState'.
void _transitionState(RecipientStateEnum endState,
boost::optional<Timestamp> fetchTimestamp = boost::none,
boost::optional<Status> abortReason = boost::none);
void _transitionStateAndUpdateCoordinator(RecipientStateEnum endState,
boost::optional<Status> abortReason = boost::none);
// Inserts 'doc' on-disk and sets '_replacementDoc' in-memory.
void _insertRecipientDocument(const ReshardingRecipientDocument& doc);
// Updates the recipient document on-disk and in-memory with the 'replacementDoc.'
void _updateRecipientDocument(ReshardingRecipientDocument&& replacementDoc);
// Removes the local recipient document from disk and clears the in-memory state.
void _removeRecipientDocument();
// Removes any docs from the oplog applier progress and txn applier progress collections that
// are associated with the in-progress operation. Also drops all oplog buffer collections and
// all conflict stash collections that are associated with the in-progress operation.
void _dropOplogCollections(OperationContext* opCtx);
// Initializes the txn cloners for this resharding operation.
void _initTxnCloner(OperationContext* opCtx, const Timestamp& fetchTimestamp);
// The in-memory representation of the underlying document in
// config.localReshardingOperations.recipient.
ReshardingRecipientDocument _recipientDoc;
// The id both for the resharding operation and for the primary-only-service instance.
const UUID _id;
std::unique_ptr<ReshardingCollectionCloner> _collectionCloner;
std::vector<std::unique_ptr<ReshardingTxnCloner>> _txnCloners;
std::vector<std::unique_ptr<ReshardingOplogApplier>> _oplogAppliers;
std::vector<std::unique_ptr<ThreadPool>> _oplogApplierWorkers;
// The ReshardingOplogFetcher must be destructed before the corresponding ReshardingOplogApplier
// to ensure the future returned by awaitInsert() is always eventually readied.
std::vector<std::unique_ptr<ReshardingOplogFetcher>> _oplogFetchers;
std::shared_ptr<executor::TaskExecutor> _oplogFetcherExecutor;
std::vector<ExecutorFuture<void>> _oplogFetcherFutures;
// Protects the promises below
Mutex _mutex = MONGO_MAKE_LATCH("ReshardingRecipient::_mutex");
// Each promise below corresponds to a state on the recipient state machine. They are listed in
// ascending order, such that the first promise below will be the first promise fulfilled.
SharedPromise<void> _coordinatorHasDecisionPersisted;
SharedPromise<void> _completionPromise;
};
} // namespace mongo
|
