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
|
/**
* Copyright (C) 2019-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/platform/basic.h"
#include "mongo/db/transaction_reaper_d.h"
#include "mongo/bson/bsonmisc.h"
#include "mongo/db/dbdirectclient.h"
#include "mongo/db/operation_context.h"
#include "mongo/db/ops/write_ops.h"
#include "mongo/db/session_txn_record_gen.h"
#include "mongo/db/sessions_collection.h"
#include "mongo/s/write_ops/batched_command_response.h"
#include "mongo/util/scopeguard.h"
namespace mongo {
namespace {
const auto kIdProjection = BSON(SessionTxnRecord::kSessionIdFieldName << 1);
const auto kSortById = BSON(SessionTxnRecord::kSessionIdFieldName << 1);
const auto kLastWriteDateFieldName = SessionTxnRecord::kLastWriteDateFieldName;
/**
* Removes the specified set of session ids from the persistent sessions collection and returns the
* number of sessions actually removed.
*/
int removeSessionsTransactionRecords(OperationContext* opCtx,
SessionsCollection& sessionsCollection,
const LogicalSessionIdSet& sessionIdsToRemove) {
if (sessionIdsToRemove.empty()) {
return 0;
}
// From the passed-in sessions, find the ones which are actually expired/removed
auto expiredSessionIds =
uassertStatusOK(sessionsCollection.findRemovedSessions(opCtx, sessionIdsToRemove));
write_ops::Delete deleteOp(NamespaceString::kSessionTransactionsTableNamespace);
deleteOp.setWriteCommandBase([] {
write_ops::WriteCommandBase base;
base.setOrdered(false);
return base;
}());
deleteOp.setDeletes([&] {
std::vector<write_ops::DeleteOpEntry> entries;
for (auto it = expiredSessionIds.begin(); it != expiredSessionIds.end(); ++it) {
entries.emplace_back(BSON(LogicalSessionRecord::kIdFieldName << it->toBSON()),
false /* multi = false */);
}
return entries;
}());
BSONObj result;
DBDirectClient client(opCtx);
client.runCommand(NamespaceString::kSessionTransactionsTableNamespace.db().toString(),
deleteOp.toBSON({}),
result);
BatchedCommandResponse response;
std::string errmsg;
uassert(ErrorCodes::FailedToParse,
str::stream() << "Failed to parse response " << result,
response.parseBSON(result, &errmsg));
uassertStatusOK(response.getTopLevelStatus());
return response.getN();
}
} // namespace
int TransactionReaperD::reapSessionsOlderThan(OperationContext* opCtx,
SessionsCollection& sessionsCollection,
Date_t possiblyExpired) {
// Scan for records older than the minimum lifetime and uses a sort to walk the '_id' index
DBDirectClient client(opCtx);
auto cursor =
client.query(NamespaceString::kSessionTransactionsTableNamespace,
Query(BSON(kLastWriteDateFieldName << LT << possiblyExpired)).sort(kSortById),
0,
0,
&kIdProjection);
// The max batch size is chosen so that a single batch won't exceed the 16MB BSON object
// size limit
LogicalSessionIdSet lsids;
const int kMaxBatchSize = 10'000;
int numReaped = 0;
while (cursor->more()) {
auto transactionSession = SessionsCollectionFetchResultIndividualResult::parse(
"TransactionSession"_sd, cursor->next());
lsids.insert(transactionSession.get_id());
if (lsids.size() > kMaxBatchSize) {
numReaped += removeSessionsTransactionRecords(opCtx, sessionsCollection, lsids);
lsids.clear();
}
}
numReaped += removeSessionsTransactionRecords(opCtx, sessionsCollection, lsids);
return numReaped;
}
} // namespace mongo
|
