MySQL 8.0.31
Source Code Documentation
log0consumer.h
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27/**************************************************/ /**
28 @file include/log0consumer.h
29
30 Redo log functions and types related to the log consumption.
31
32 *******************************************************/
33
34#ifndef log0consumer_h
35#define log0consumer_h
36
37#include "log0types.h" /* lsn_t, log_t& */
38
40 public:
41 virtual ~Log_consumer() {}
42
43 /** @return Name of this consumer. */
44 virtual const std::string &get_name() const = 0;
45
46 /** @return Maximum LSN up to which this consumer has consumed redo. */
47 virtual lsn_t get_consumed_lsn() const = 0;
48
49 /** Request the log consumer to consume faster.
50 @remarks This is called whenever the redo log consumer
51 is the most lagging one and it is critical to consume
52 the oldest redo log file. */
53 virtual void consumption_requested() = 0;
54};
55
57 public:
58 explicit Log_user_consumer(const std::string &name);
59
60 const std::string &get_name() const override;
61
62 /** Set the lsn reported by get_consumed_lsn() to the given value.
63 It is required that the given value is greater or equal to the value
64 currently reported by the get_consumed_lsn().
65 @param[in] consumed_lsn the given lsn to report */
66 void set_consumed_lsn(lsn_t consumed_lsn);
67
68 lsn_t get_consumed_lsn() const override;
69
70 void consumption_requested() override;
71
72 private:
73 /** Name of this consumer (saved value from ctor). */
74 const std::string m_name;
75
76 /** Value reported by get_consumed_lsn().
77 Set by set_consumed_lsn(lsn). */
79};
80
82 public:
83 explicit Log_checkpoint_consumer(log_t &log);
84
85 const std::string &get_name() const override;
86
87 lsn_t get_consumed_lsn() const override;
88
89 void consumption_requested() override;
90
91 private:
93};
94
95/** Register the given redo log consumer.
96@param[in,out] log redo log
97@param[in] log_consumer redo log consumer to register */
98void log_consumer_register(log_t &log, Log_consumer *log_consumer);
99
100/** Unregister the given redo log consumer.
101@param[in,out] log redo log
102@param[in] log_consumer redo log consumer to unregister */
103void log_consumer_unregister(log_t &log, Log_consumer *log_consumer);
104
105/** Find the registered redo log consumer which has the smallest value
106reported by get_consumed_lsn() - ie. the most lagging consumer. When
107multiple consumers have the same value, any of them might be returned.
108@param[in] log the redo log
109@param[out] oldest_needed_lsn the oldest lsn needed by the most lagging consumer
110@return the most lagging consumer */
112 lsn_t &oldest_needed_lsn);
113
114#endif /* !log0consumer_h */
Definition: log0consumer.h:81
log_t & m_log
Definition: log0consumer.h:92
void consumption_requested() override
Request the log consumer to consume faster.
Definition: log0consumer.cc:68
const std::string & get_name() const override
Definition: log0consumer.cc:59
lsn_t get_consumed_lsn() const override
Definition: log0consumer.cc:64
Log_checkpoint_consumer(log_t &log)
Definition: log0consumer.cc:57
Definition: log0consumer.h:39
virtual ~Log_consumer()
Definition: log0consumer.h:41
virtual void consumption_requested()=0
Request the log consumer to consume faster.
virtual const std::string & get_name() const =0
virtual lsn_t get_consumed_lsn() const =0
Definition: log0consumer.h:56
void consumption_requested() override
Request the log consumer to consume faster.
Definition: log0consumer.cc:55
const std::string m_name
Name of this consumer (saved value from ctor).
Definition: log0consumer.h:74
Log_user_consumer(const std::string &name)
Definition: log0consumer.cc:41
void set_consumed_lsn(lsn_t consumed_lsn)
Set the lsn reported by get_consumed_lsn() to the given value.
Definition: log0consumer.cc:45
lsn_t get_consumed_lsn() const override
Definition: log0consumer.cc:53
const std::string & get_name() const override
Definition: log0consumer.cc:43
lsn_t m_consumed_lsn
Value reported by get_consumed_lsn().
Definition: log0consumer.h:78
void log_consumer_register(log_t &log, Log_consumer *log_consumer)
Register the given redo log consumer.
Definition: log0consumer.cc:72
void log_consumer_unregister(log_t &log, Log_consumer *log_consumer)
Unregister the given redo log consumer.
Definition: log0consumer.cc:78
Log_consumer * log_consumer_get_oldest(const log_t &log, lsn_t &oldest_needed_lsn)
Find the registered redo log consumer which has the smallest value reported by get_consumed_lsn() - i...
Definition: log0consumer.cc:85
Redo log basic types.
uint64_t lsn_t
Type used for all log sequence number storage and arithmetic.
Definition: log0types.h:62
case opt name
Definition: sslopt-case.h:32
Redo log - single data structure with state of the redo log system.
Definition: log0sys.h:74