MySQL  8.0.27
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rpl_context.h
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22 
23 #ifndef RPL_SESSION_H
24 #define RPL_SESSION_H
25 
26 #include <sys/types.h>
27 #include <memory>
28 
29 #include "my_inttypes.h" // IWYU pragma: keep
30 
31 #include "sql/system_variables.h"
32 
33 class Gtid_set;
34 class Sid_map;
35 class THD;
36 struct Gtid;
37 
38 /** Type of replication channel thread/transaction might be associated to*/
40  NO_CHANNEL_INFO = 0, // No information exists about the channel
41  RPL_STANDARD_CHANNEL = 1, // It is a standard replication channel
42  GR_APPLIER_CHANNEL = 2, // It is a GR applier channel
43  GR_RECOVERY_CHANNEL = 3 // It is a GR recovery channel
44 };
45 
46 /**
47  This class is an interface for session consistency instrumentation
48  in the server. It holds the context information for a given session.
49 
50  It does not require locking since access to this content is mutually
51  exclusive by design (only one thread reading or writing to this object
52  at a time).
53  */
55  public:
56  /**
57  This is an interface to be implemented by classes that want to listen
58  to changes to this context. This can be used, for instance, by the
59  session tracker gtids to become aware of ctx modifications.
60  */
62  public:
63  Ctx_change_listener() = default;
64  virtual ~Ctx_change_listener() = default;
65  virtual void notify_session_gtids_ctx_change() = 0;
66 
67  private:
68  // not implemented
71  };
72 
73  private:
74  /*
75  Local sid_map to enable a lock free m_gtid_set.
76  */
78 
79  /**
80  Set holding the transaction identifiers of the gtids
81  to reply back on the response packet.
82 
83  Lifecycle: Emptied after the reply is sent back to the application. Remains
84  empty until:
85  - a RW transaction commits and a GTID is written to the binary log.
86  - a RO transaction is issued, the consistency level is set to "Check
87  Potential Writes" and the transaction is committed.
88  */
90 
91  /**
92  If a listener is registered, e.g., the session track gtids, then this
93  points to an instance of such listener.
94 
95  Since this context is valid only for one session, there is no need
96  to protect this with locks.
97  */
99 
100  /**
101  Keeps track of the current session track gtids, so that we capture
102  according to what was set before. For instance, if the user does:
103  SET @@SESSION.SESSION_TRACK_GTIDS='ALL_GTIDS';
104  ...
105  SET @@SESSION.SESSION_TRACK_GTIDS='OWN_GTID';
106 
107  The last statement should return a set of GTIDs.
108  */
110 
111  protected:
112  /*
113  Auxiliary function to determine if GTID collection should take place
114  when it is invoked. It takes into consideration the gtid_mode and
115  the current session context.
116 
117  @param thd the thread context.
118  @return true if should collect gtids, false otherwise.
119  */
120  inline bool shall_collect(const THD *thd);
121 
122  /**
123  Auxiliary function that allows notification of ctx change listeners.
124  */
127  }
128 
129  public:
130  /**
131  Simple constructor.
132  */
134 
135  /**
136  The destructor. Deletes the m_gtid_set and the sid_map.
137  */
139 
140  /**
141  Registers the listener. The pointer MUST not be NULL.
142 
143  @param listener a pointer to the listener to register.
144  @param thd THD context associated to this listener.
145  */
148 
149  /**
150  Unregisters the listener. The listener MUST have registered previously.
151 
152  @param listener a pointer to the listener to register.
153  */
156 
157  /**
158  This member function MUST return a reference to the set of collected
159  GTIDs so far.
160 
161  @return the set of collected GTIDs so far.
162  */
163  inline Gtid_set *state() { return m_gtid_set; }
164 
165  /**
166  This function MUST be called after the response packet is set to the
167  client connected. The implementation may act on the collected state
168  for instance to do garbage collection.
169 
170  @param thd The thread context.
171  * @return true on error, false otherwise.
172  */
173  virtual bool notify_after_response_packet(const THD *thd);
174 
175  /**
176  This function SHALL be called once the GTID for the given transaction has
177  has been added to GTID_EXECUTED.
178 
179  This function SHALL store the data if the
180  thd->variables.session_track_gtids is set to a value other than NONE.
181 
182  @param thd The thread context.
183  @return true on error, false otherwise.
184  */
185  virtual bool notify_after_gtid_executed_update(const THD *thd);
186 
187  /**
188  This function MUST be called after a transaction is committed
189  in the server. It should be called regardless whether it is a
190  RO or RW transaction. Also, DDLs, DDS are considered transaction
191  for what is worth.
192 
193  This function SHALL store relevant data for the session consistency.
194 
195  @param thd The thread context.
196  @return true on error, false otherwise.
197  */
198  virtual bool notify_after_transaction_commit(const THD *thd);
199 
200  virtual bool notify_after_xa_prepare(const THD *thd) {
202  }
203 
204  /**
205  Update session tracker (m_curr_session_track_gtids) from thd.
206  */
208 
209  private:
210  // not implemented
213  const Session_consistency_gtids_ctx &rsc);
214 };
215 
216 /*
217  This object encapsulates the state kept between transactions of the same
218  client in order to compute logical timestamps based on WRITESET_SESSION.
219 */
221  public:
223 
224  void set_last_session_sequence_number(int64 sequence_number) {
225  m_last_session_sequence_number = sequence_number;
226  }
227 
230  }
231 
232  private:
234 };
235 
236 /**
237  This class tracks the last used GTID per session.
238 */
240  public:
243 
244  /**
245  Set the last used GTID the session.
246 
247  @param[in] gtid the used gtid.
248  */
249  void set_last_used_gtid(const Gtid &gtid);
250 
251  /**
252  Get the last used GTID the session.
253 
254  @param[out] gtid the used gtid.
255  */
256  void get_last_used_gtid(Gtid &gtid);
257 
258  private:
259  std::unique_ptr<Gtid> m_last_used_gtid;
260 };
261 
263  public:
264  static const size_t DEFAULT_COMPRESSION_BUFFER_SIZE;
265 
268 
270  THD *session);
271 
272  protected:
274 };
275 
276 /*
277  This class SHALL encapsulate the replication context associated with the THD
278  object.
279  */
281  private:
286  /** If this thread is a channel, what is its type*/
288 
291 
292  public:
294 
296  return m_session_gtids_ctx;
297  }
298 
301  }
302 
305  }
306 
308 
309  void set_rpl_channel_type(enum_rpl_channel_type rpl_channel_type_arg) {
310  rpl_channel_type = rpl_channel_type_arg;
311  }
312 
315  }
316 };
317 
318 #endif /* RPL_SESSION_H */
Definition: rpl_context.h:220
void set_last_session_sequence_number(int64 sequence_number)
Definition: rpl_context.h:224
int64 m_last_session_sequence_number
Definition: rpl_context.h:233
Dependency_tracker_ctx()
Definition: rpl_context.h:222
int64 get_last_session_sequence_number()
Definition: rpl_context.h:228
Represents a set of GTIDs.
Definition: rpl_gtid.h:1435
This class tracks the last used GTID per session.
Definition: rpl_context.h:239
Last_used_gtid_tracker_ctx()
Definition: rpl_context.cc:189
void get_last_used_gtid(Gtid &gtid)
Get the last used GTID the session.
Definition: rpl_context.cc:199
std::unique_ptr< Gtid > m_last_used_gtid
Definition: rpl_context.h:259
void set_last_used_gtid(const Gtid &gtid)
Set the last used GTID the session.
Definition: rpl_context.cc:195
virtual ~Last_used_gtid_tracker_ctx()
Definition: rpl_context.h:280
Transaction_compression_ctx & transaction_compression_ctx()
Definition: rpl_context.h:313
Session_consistency_gtids_ctx & session_gtids_ctx()
Definition: rpl_context.h:295
Last_used_gtid_tracker_ctx m_last_used_gtid_tracker_ctx
Definition: rpl_context.h:284
Transaction_compression_ctx m_transaction_compression_ctx
Definition: rpl_context.h:285
Dependency_tracker_ctx m_dependency_tracker_ctx
Definition: rpl_context.h:283
Session_consistency_gtids_ctx m_session_gtids_ctx
Definition: rpl_context.h:282
Dependency_tracker_ctx & dependency_tracker_ctx()
Definition: rpl_context.h:299
enum_rpl_channel_type get_rpl_channel_type()
Definition: rpl_context.h:307
Last_used_gtid_tracker_ctx & last_used_gtid_tracker_ctx()
Definition: rpl_context.h:303
Rpl_thd_context()
Definition: rpl_context.h:293
void set_rpl_channel_type(enum_rpl_channel_type rpl_channel_type_arg)
Definition: rpl_context.h:309
Rpl_thd_context & operator=(const Rpl_thd_context &rsc)
Rpl_thd_context(const Rpl_thd_context &rsc)
enum_rpl_channel_type rpl_channel_type
If this thread is a channel, what is its type.
Definition: rpl_context.h:287
This is an interface to be implemented by classes that want to listen to changes to this context.
Definition: rpl_context.h:61
Ctx_change_listener & operator=(const Ctx_change_listener &rsc)
Ctx_change_listener(const Ctx_change_listener &rsc)
This class is an interface for session consistency instrumentation in the server.
Definition: rpl_context.h:54
virtual bool notify_after_xa_prepare(const THD *thd)
Definition: rpl_context.h:200
virtual bool notify_after_transaction_commit(const THD *thd)
This function MUST be called after a transaction is committed in the server.
Definition: rpl_context.cc:67
bool shall_collect(const THD *thd)
Definition: rpl_context.cc:55
Session_consistency_gtids_ctx::Ctx_change_listener * m_listener
If a listener is registered, e.g., the session track gtids, then this points to an instance of such l...
Definition: rpl_context.h:98
virtual bool notify_after_gtid_executed_update(const THD *thd)
This function SHALL be called once the GTID for the given transaction has has been added to GTID_EXEC...
Definition: rpl_context.cc:93
Gtid_set * state()
This member function MUST return a reference to the set of collected GTIDs so far.
Definition: rpl_context.h:163
void unregister_ctx_change_listener(Session_consistency_gtids_ctx::Ctx_change_listener *listener)
Unregisters the listener.
Definition: rpl_context.cc:175
Sid_map * m_sid_map
Definition: rpl_context.h:77
virtual bool notify_after_response_packet(const THD *thd)
This function MUST be called after the response packet is set to the client connected.
Definition: rpl_context.cc:141
Gtid_set * m_gtid_set
Set holding the transaction identifiers of the gtids to reply back on the response packet.
Definition: rpl_context.h:89
void notify_ctx_change_listener()
Auxiliary function that allows notification of ctx change listeners.
Definition: rpl_context.h:125
Session_consistency_gtids_ctx & operator=(const Session_consistency_gtids_ctx &rsc)
void update_tracking_activeness_from_session_variable(const THD *thd)
Update session tracker (m_curr_session_track_gtids) from thd.
Definition: rpl_context.cc:137
virtual ~Session_consistency_gtids_ctx()
The destructor.
Definition: rpl_context.cc:43
ulong m_curr_session_track_gtids
Keeps track of the current session track gtids, so that we capture according to what was set before.
Definition: rpl_context.h:109
Session_consistency_gtids_ctx(const Session_consistency_gtids_ctx &rsc)
void register_ctx_change_listener(Session_consistency_gtids_ctx::Ctx_change_listener *listener, THD *thd)
Registers the listener.
Definition: rpl_context.cc:157
Session_consistency_gtids_ctx()
Simple constructor.
Definition: rpl_context.cc:37
Represents a bidirectional map between SID and SIDNO.
Definition: rpl_gtid.h:705
For each client connection we create a separate thread with THD serving as a thread/connection descri...
Definition: sql_class.h:821
Definition: rpl_context.h:262
virtual ~Transaction_compression_ctx()
Definition: rpl_context.cc:210
binary_log::transaction::compression::Compressor * get_compressor(THD *session)
Definition: rpl_context.cc:220
binary_log::transaction::compression::Compressor * m_compressor
Definition: rpl_context.h:273
static const size_t DEFAULT_COMPRESSION_BUFFER_SIZE
Definition: rpl_context.h:264
Transaction_compression_ctx()
Definition: rpl_context.cc:207
The base compressor abstract class.
Definition: base.h:145
Some integer typedefs for easier portability.
int64_t int64
Definition: my_inttypes.h:67
enum_rpl_channel_type
Type of replication channel thread/transaction might be associated to.
Definition: rpl_context.h:39
@ NO_CHANNEL_INFO
Definition: rpl_context.h:40
@ GR_RECOVERY_CHANNEL
Definition: rpl_context.h:43
@ RPL_STANDARD_CHANNEL
Definition: rpl_context.h:41
@ GR_APPLIER_CHANNEL
Definition: rpl_context.h:42
TODO: Move this structure to libbinlogevents/include/control_events.h when we start using C++11.
Definition: rpl_gtid.h:1047