MySQL 8.4.3
Source Code Documentation
page_track_service.h
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1/* Copyright (c) 2018, 2024, Oracle and/or its affiliates.
2
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16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
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20 You should have received a copy of the GNU General Public License
21 along with this program; if not, write to the Free Software
22 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
23
24/**
25 @brief
26
27 This defines the API used to call functions to the page tracking service.
28 When implementing such a service, refer to mysql_page_track.h instead!
29
30*/
31
32#ifndef MYSQL_PAGE_TRACK_SERVICE_H
33#define MYSQL_PAGE_TRACK_SERVICE_H
34
36#include <functional>
37
38#include <stddef.h>
39#include <stdint.h>
40
41#ifdef __cplusplus
42class THD;
43#define MYSQL_THD THD *
44#else
45#define MYSQL_THD void *
46#endif
47
48/**
49 SE for the page tracking. Currently supports only in InnoDB.
50*/
52
53/**
54 Page tracking callback function.
55
56 @param[in] thd Current thread context
57 @param[in] buffer buffer filled with 8 byte page ids; the format is
58 specific to SE. For InnoDB it is space_id (4 bytes) followed by page number
59 (4 bytes)
60 @param[in] buf_len length of buffer in bytes
61 @param[in] num_pages number of valid page IDs in buffer
62 @param[in,out] user_ctx user context passed to page tracking function
63
64 @return Operation status.
65*/
66typedef int (*Page_Track_Callback)(MYSQL_THD thd, const unsigned char *buffer,
67 size_t buf_len, int num_pages,
68 void *user_ctx);
69
70BEGIN_SERVICE_DEFINITION(mysql_page_track)
71
72/**
73 Service API to start page tracking
74
75 @param[in] opaque_thd Current thread context.
76 @param[in] se_type SE for which to enable tracking
77 @param[out] start_id SE specific sequence number [LSN for InnoDB]
78 indicating when the tracking was started
79
80 @return Operation status.
81 @retval 0 Success
82 @retval other ER_* mysql error. Get error details from THD.
83*/
84
86 (MYSQL_THD opaque_thd, Page_Track_SE se_type,
87 uint64_t *start_id));
88
89/**
90 Service API to stop page tracking
91
92 @param[in] opaque_thd Current thread context.
93 @param[in] se_type SE for which to enable tracking
94 @param[out] stop_id SE specific sequence number [LSN for InnoDB]
95 indicating when the tracking was stopped
96
97 @return Operation status.
98 @retval 0 Success
99 @retval other ER_* mysql error. Get error details from THD.
100*/
101
102DECLARE_METHOD(int, stop,
103 (MYSQL_THD opaque_thd, Page_Track_SE se_type,
104 uint64_t *stop_id));
105
106/**
107 Service API to purge page tracking data.
108
109 @param[in] opaque_thd Current thread context.
110 @param[in] se_type SE for which to enable tracking
111 @param[in,out] purge_id SE specific sequence number [LSN for InnoDB]
112 initially indicating till where the data needs to be purged and finally
113 updated to until where it was actually purged
114
115 @return Operation status.
116 @retval 0 Success
117 @retval other ER_* mysql error. Get error details from THD.
118*/
120 (MYSQL_THD opaque_thd, Page_Track_SE se_type,
121 uint64_t *purge_id));
122
123/**
124 Service API to get tracked pages
125
126 @param[in] opaque_thd Current thread context.
127 @param[in] se_type SE for which to enable tracking
128 @param[in,out] start_id SE specific sequence number [LSN for InnoDB] from
129 where the pages tracked would be returned.
130 @note The range might get expanded and the actual start_id used for the
131 querying will be updated.
132 @param[in,out] stop_id SE specific sequence number [LSN for InnoDB]
133 until where the pages tracked would be returned.
134 @note The range might get expanded and the actual stop_id used for the
135 querying will be updated.
136 @param[out] buffer allocated buffer to copy page IDs
137 @param[in] buffer_len length of buffer in bytes
138 @param[in] cbk_func callback function return page IDs
139 @param[in] cbk_ctx caller's context for callback
140
141 @return Operation status.
142 @retval 0 Success
143 @retval other ER_* mysql error. Get error details from THD.
144*/
145
146DECLARE_METHOD(int, get_page_ids,
147 (MYSQL_THD opaque_thd, Page_Track_SE se_type, uint64_t *start_id,
148 uint64_t *stop_id, unsigned char *buffer, size_t buffer_len,
149 Page_Track_Callback cbk_func, void *cbk_ctx));
150
151/**
152 Service API to get approximate number of pages tracked in the given range.
153
154 @param[in] opaque_thd Current thread context.
155 @param[in] se_type SE for which to enable tracking
156 @param[in,out] start_id SE specific sequence number [LSN for InnoDB] from
157 where the pages tracked would be returned.
158 @note the range might get expanded and the actual start_id used for the
159 querying will be updated.
160 @param[in,out] stop_id SE specific sequence number [LSN for InnoDB]
161 until where the pages tracked would be returned.
162 @note the range might get expanded and the actual stop_id used for the
163 querying will be updated.
164 @param[out] num_pages number of pages tracked
165
166 @return Operation status.
167 @retval 0 Success
168 @retval other ER_* mysql error. Get error details from THD.
169*/
170DECLARE_METHOD(int, get_num_page_ids,
171 (MYSQL_THD opaque_thd, Page_Track_SE se_type, uint64_t *start_id,
172 uint64_t *stop_id, uint64_t *num_pages));
173
174/**
175 API to check if the page tracking is active or not and to return start id if
176 it's active.
177
178 @param[in] opaque_thd Current thread context.
179 @param[in] se_type SE for which to enable tracking
180 @param[out] initial_start_id SE specific sequence number [LSN for
181 InnoDB] which denotes the start id at which page tracking was started if it's
182 active
183 @param[out] last_start_id SE specific sequence number [LSN for
184 InnoDB] which denotes the start id the last time the start request was issued
185 @return if page tracking is active or not
186 @retval true if page tracking is active
187 @retval false if page tracking is not active
188*/
189DECLARE_METHOD(int, get_status,
190 (MYSQL_THD opaque_thd, Page_Track_SE se_type,
191 uint64_t *initial_start_id, uint64_t *last_start_id));
192
193END_SERVICE_DEFINITION(mysql_page_track)
194
195#endif
For each client connection we create a separate thread with THD serving as a thread/connection descri...
Definition: sql_lexer_thd.h:36
static void start(mysql_harness::PluginFuncEnv *env)
Definition: http_auth_backend_plugin.cc:180
void purge(lob::DeleteContext *ctx, dict_index_t *index, trx_id_t trxid, undo_no_t undo_no, ulint rec_type, const upd_field_t *uf, purge_node_t *node)
Purge an LOB (either of compressed or uncompressed).
Definition: lob0purge.cc:414
mutable_buffer buffer(void *p, size_t n) noexcept
Definition: buffer.h:418
#define MYSQL_THD
Definition: page_track_service.h:43
int(* Page_Track_Callback)(MYSQL_THD thd, const unsigned char *buffer, size_t buf_len, int num_pages, void *user_ctx)
Page tracking callback function.
Definition: page_track_service.h:66
Page_Track_SE
SE for the page tracking.
Definition: page_track_service.h:51
@ PAGE_TRACK_SE_INNODB
Definition: page_track_service.h:51
#define DECLARE_METHOD(retval, name, args)
Declares a method as a part of the Service definition.
Definition: service.h:103
#define END_SERVICE_DEFINITION(name)
A macro to end the last Service definition started with the BEGIN_SERVICE_DEFINITION macro.
Definition: service.h:91
#define BEGIN_SERVICE_DEFINITION(name)
Declares a new Service.
Definition: service.h:86