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
|
/**
* Copyright (C) 2017 MongoDB Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* 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
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* 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 GNU Affero General 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/logical_session_cache.h"
#include "mongo/db/logical_session_id.h"
#include "mongo/db/refresh_sessions_gen.h"
#include "mongo/db/service_liaison.h"
#include "mongo/db/sessions_collection.h"
#include "mongo/db/time_proof_service.h"
#include "mongo/db/transaction_reaper.h"
#include "mongo/platform/atomic_word.h"
#include "mongo/stdx/thread.h"
#include "mongo/util/lru_cache.h"
namespace mongo {
class Client;
class OperationContext;
class ServiceContext;
extern int logicalSessionRefreshMinutes;
/**
* A thread-safe cache structure for logical session records.
*
* The cache takes ownership of the passed-in ServiceLiaison and
* SessionsCollection helper types.
*/
class LogicalSessionCacheImpl final : public LogicalSessionCache {
public:
static constexpr Minutes kLogicalSessionDefaultRefresh = Minutes(5);
/**
* An Options type to support the LogicalSessionCacheImpl.
*/
struct Options {
Options(){};
/**
* A timeout value to use for sessions in the cache, in minutes.
*
* By default, this is set to 30 minutes.
*
* May be set with --setParameter localLogicalSessionTimeoutMinutes=X.
*/
Minutes sessionTimeout = Minutes(localLogicalSessionTimeoutMinutes);
/**
* The interval over which the cache will refresh session records.
*
* By default, this is set to every 5 minutes. If the caller is
* setting the sessionTimeout by hand, it is suggested that they
* consider also setting the refresh interval accordingly.
*
* May be set with --setParameter logicalSessionRefreshMinutes=X.
*/
Minutes refreshInterval = Minutes(logicalSessionRefreshMinutes);
};
/**
* Construct a new session cache.
*/
explicit LogicalSessionCacheImpl(std::unique_ptr<ServiceLiaison> service,
std::shared_ptr<SessionsCollection> collection,
std::shared_ptr<TransactionReaper> transactionReaper,
Options options = Options{});
LogicalSessionCacheImpl(const LogicalSessionCacheImpl&) = delete;
LogicalSessionCacheImpl& operator=(const LogicalSessionCacheImpl&) = delete;
~LogicalSessionCacheImpl();
Status promote(LogicalSessionId lsid) override;
Status startSession(OperationContext* opCtx, LogicalSessionRecord record) override;
Status refreshSessions(OperationContext* opCtx,
const RefreshSessionsCmdFromClient& cmd) override;
Status refreshSessions(OperationContext* opCtx,
const RefreshSessionsCmdFromClusterMember& cmd) override;
Status vivify(OperationContext* opCtx, const LogicalSessionId& lsid) override;
Status refreshNow(Client* client) override;
Status reapNow(Client* client) override;
Date_t now() override;
size_t size() override;
std::vector<LogicalSessionId> listIds() const override;
std::vector<LogicalSessionId> listIds(
const std::vector<SHA256Block>& userDigest) const override;
boost::optional<LogicalSessionRecord> peekCached(const LogicalSessionId& id) const override;
void endSessions(const LogicalSessionIdSet& sessions) override;
LogicalSessionCacheStats getStats() override;
private:
/**
* Internal methods to handle scheduling and perform refreshes for active
* session records contained within the cache.
*/
void _periodicRefresh(Client* client);
void _refresh(Client* client);
void _periodicReap(Client* client);
Status _reap(Client* client);
/**
* Returns true if a record has passed its given expiration.
*/
bool _isDead(const LogicalSessionRecord& record, Date_t now) const;
/**
* Takes the lock and inserts the given record into the cache.
*/
Status _addToCache(LogicalSessionRecord record);
const Minutes _refreshInterval;
const Minutes _sessionTimeout;
// This value is only modified under the lock, and is modified
// automatically by the background jobs.
LogicalSessionCacheStats _stats;
std::unique_ptr<ServiceLiaison> _service;
std::shared_ptr<SessionsCollection> _sessionsColl;
mutable stdx::mutex _reaperMutex;
std::shared_ptr<TransactionReaper> _transactionReaper;
mutable stdx::mutex _cacheMutex;
LogicalSessionIdMap<LogicalSessionRecord> _activeSessions;
LogicalSessionIdSet _endingSessions;
Date_t lastRefreshTime;
};
} // namespace mongo
|
