最近有客户发现使用自增主键的表，在业务使用delete删除了数据后，实际的表文件比数据要大；心中很是疑惑，到底是怎么回事
一、MySQL存储数据
MySQL使用聚簇索引存储全表数据，如果不存在主键会生成隐式主键来组织聚簇索引；在8.0.30版本MySQL引入了不可见主键，也就是说MySQL 会在没有显示定义主键的InnoDB表上自动生成不可见的主键，由参数sql_generate_invisible_primary_key 控制，默认关闭，表示禁用，如果需要使用该特性，则需显式开启。
那么在聚簇索引上的每层数据页以及页面中的记录都是按照主键值从小到大的顺序排序，如果存在自增主键或者主键递增的情况下，后面插入的主键值越来越大的情况下都是在最后，这样可以防止主键忽大忽小情况下的页分裂；
在这种情况下，如果有数据删除产生的页空隙就会无法重复利用，但MySQL还有一个机制是索引页在删除到一定比列的情况下会尝试与相邻页合并，大概原理如下：
页 A 在删除一些记录后，此页里剩余记录对页 A 的占用小于 MERGE_THRESHOLD 设定的值，此时刚好页 A 相邻的一个页 C，数据占用也不到 50%，这时候 MySQL 会把页 C 的记录并入页 A，之后页 C 的空间就被释放，不包含任何数据，页 C 就可用于以后新记录的写入，避免空间的浪费。
但递增主键的表delete 肯定会存在一定数量的表碎片，这种情况下可以手动通过analyze table、alter table engine=innodb进行碎片整理。
二、索引页合并怎么设置的呢？
上节说到索引页合并，那么索引页合并的阈值是如何设置的呢？
MySQL通过MERGE_THRESHOLD 来配置索引页合并的阈值，这个参数在MySQL中是写入到硬编码中，默认值为50；当页面填充比例小于MERGE_THRESHOLD参数时，会尝试与相邻页进行页合并。
You can configure the
MERGE_THRESHOLDvalue for index pages. If the “page-full” percentage for an index page falls below theMERGE_THRESHOLDvalue when a row is deleted or when a row is shortened by anUPDATEoperation,InnoDBattempts to merge the index page with a neighboring index page. The defaultMERGE_THRESHOLDvalue is 50, which is the previously hardcoded value. The minimumMERGE_THRESHOLDvalue is 1 and the maximum value is 50.
既然是通过硬编码写入的，那么还有其他的方式可以配置索引页合并的吗？
我们通过SELECT * FROM information_schema.INNODB_SYS_INDEXES 可以查看索引的合并配置，那么在建表或者新建索引的时候是否可以指定页合并的配置呢？是否可以通过alter 修改页合并的配置呢？
当然是可以的。可以通过一下几种方式配置表或者索引的合并阈值
2.1 create table 通过table_option COMMENT 子句为表设置MERGE_THRESHOLD值
你可以使用`CREATE TABLE`语句的`COMMENT`子句中的`table_option`，为表设置`MERGE_THRESHOLD`值。例如：
CREATE TABLE t1 (
id INT,
KEY id_index (id)
) COMMENT='MERGE_THRESHOLD=45';也可以使用带有 ALTER TABLE 的 table_option COMMENT 子句，为现有表设置 MERGE_THRESHOLD 值：
CREATE TABLE t1 (
id INT,
KEY id_index (id)
);
ALTER TABLE t1 COMMENT='MERGE_THRESHOLD=40';2.2 在create table、alter table 或create index中使用 index_option COMENT子句修改
使用CREATE TABLE为单个索引设置MERGE_THRESHOLD：
CREATE TABLE t1 (
id INT,
KEY id_index (id) COMMENT 'MERGE_THRESHOLD=40'
);使用ALTER TABLE为单个索引设置MERGE_THRESHOLD：
CREATE TABLE t1 (
id INT,
KEY id_index (id)
);
ALTER TABLE t1 DROP KEY id_index;
ALTER TABLE t1 ADD KEY id_index (id) COMMENT 'MERGE_THRESHOLD=40';使用 CREATE INDEX 为单个索引设置 MERGE_THRESHOLD：
CREATE TABLE t1 (id INT);
CREATE INDEX id_index ON t1 (id) COMMENT 'MERGE_THRESHOLD=40';⚠️注意：您能在gen_clust_index的索引级别上修改Merge_threshold值，这是Innodb创建的InnoDB表创建的无主键或唯一键索引时创建的群集索引。只能通过为表格设置Merge_threshold来修改gen_clust_index的Merge_threshold值。
2.3 如何查看页合并的配置
可以通过查询INNODB_INDEXES表获取索引当前的MERGE_THRESHOLD值。例如：
mysql> SELECT * FROM INFORMATION_SCHEMA.INNODB_INDEXES WHERE NAME='id_index' \G
*************************** 1. row ***************************
INDEX_ID: 91
NAME: id_index
TABLE_ID: 68
TYPE: 0
N_FIELDS: 1
PAGE_NO: 4
SPACE: 57
MERGE_THRESHOLD: 40也可以使用 SHOW CREATE TABLE 查看表的 MERGE_THRESHOLD 值（前提是使用 table_option COMMENT 子句显式定义了该值）：
mysql> SHOW CREATE TABLE t2 \G
*************************** 1. row ***************************
Table: t2
Create Table: CREATE TABLE `t2` (
`id` int(11) DEFAULT NULL,
KEY `id_index` (`id`) COMMENT 'MERGE_THRESHOLD=40'
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci⚠️注意：在索引级别定义的 MERGE_THRESHOLD 值优先于为表定义的 MERGE_THRESHOLD 值。如果未定义，则MERGE_THRESHOLD默认为 50% （MERGE_THRESHOLD=50，这是以前的硬编码值。
三、如何监控页合并呢？有没有什么指标数据库呢？
INNODB_METRICS 表提供了两个计数器，可用于衡量 MERGE_THRESHOLD 设置对索引页合并的影响。
mysql> SELECT NAME, COMMENT FROM INFORMATION_SCHEMA.INNODB_METRICS
WHERE NAME like '%index_page_merge%';
+-----------------------------+----------------------------------------+
| NAME | COMMENT |
+-----------------------------+----------------------------------------+
| index_page_merge_attempts | Number of index page merge attempts |
| index_page_merge_successful | Number of successful index page merges |
+-----------------------------+----------------------------------------+这两个监控指标是如何配置的呢？
3.1 页合并监控项
ndex_page_merge_attempts 和index_page_merge_successful 监控指标默认不开启，如何开启页合并的监控计数器呢？
1. 启用、禁用和重置计数器
-- 启用监控计数器
SET GLOBAL innodb_monitor_enable = [counter-name|module_name|pattern|all];
-- 关闭监控计数器
SET GLOBAL innodb_monitor_disable = [counter-name|module_name|pattern|all];
-- 重置监控计数器
SET GLOBAL innodb_monitor_reset = [counter-name|module_name|pattern|all];
-- 重置所有计数器值。在使用之前，必须禁用计数器
SET GLOBAL innodb_monitor_reset_all = [counter-name|module_name|pattern|all];
计数器和计数器模块也可以在启动时通过MySQL服务器配置文件启用。例如，要启用log模块、metadata_table_handles_opened和metadata_table_handles_closed计数器，请在MySQL服务器配置文件的[mysqld]部分中输入以下行。
[mysqld]
innodb_monitor_enable = module_recovery,metadata_table_handles_opened,metadata_table_handles_closedz⚠️注意：由于每个计数器都会增加一定程度的运行时开销，因此在生产服务器上应谨慎使用计数器，以诊断特定问题或监控特定功能。若要使用更多指标的计数器，建议使用测试服务器或开发服务器。
2. 非默认指标开启后是否会记录到show engine innodb status中呢
经测试，这两个指标开启后不会输出到show innodb status 中；根据官方说明：默认启用的计数器与SHOW ENGINE INNODB STATUS输出中显示的计数器相对应；SHOW ENGINE INNODB STATUS输出中显示的计数器在系统级别始终启用，但对于 INNODB_METRICS表可以禁用。
-- 开启前
mysql> select * from INFORMATION_SCHEMA.INNODB_METRICS WHERE NAME like '%index_page_merge%'\G
*************************** 1. row ***************************
NAME: index_page_merge_attempts
SUBSYSTEM: index
COUNT: 0
MAX_COUNT: NULL
MIN_COUNT: NULL
AVG_COUNT: NULL
COUNT_RESET: 0
MAX_COUNT_RESET: NULL
MIN_COUNT_RESET: NULL
AVG_COUNT_RESET: NULL
TIME_ENABLED: NULL
TIME_DISABLED: NULL
TIME_ELAPSED: NULL
TIME_RESET: NULL
STATUS: disabled
TYPE: counter
COMMENT: Number of index page merge attempts
*************************** 2. row ***************************
NAME: index_page_merge_successful
SUBSYSTEM: index
COUNT: 0
MAX_COUNT: NULL
MIN_COUNT: NULL
AVG_COUNT: NULL
COUNT_RESET: 0
MAX_COUNT_RESET: NULL
MIN_COUNT_RESET: NULL
AVG_COUNT_RESET: NULL
TIME_ENABLED: NULL
TIME_DISABLED: NULL
TIME_ELAPSED: NULL
TIME_RESET: NULL
STATUS: disabled
TYPE: counter
COMMENT: Number of successful index page merges
2 rows in set (0.00 sec)
mysql>
mysql> show engine innodb status\G
*************************** 1. row ***************************
Type: InnoDB
Name:
Status:
=====================================
2025-06-13 09:39:04 0x3107d5000 INNODB MONITOR OUTPUT
=====================================
Per second averages calculated from the last 36 seconds
-----------------
BACKGROUND THREAD
-----------------
srv_master_thread loops: 1 srv_active, 0 srv_shutdown, 505058 srv_idle
srv_master_thread log flush and writes: 505037
----------
SEMAPHORES
----------
OS WAIT ARRAY INFO: reservation count 12
OS WAIT ARRAY INFO: signal count 10
RW-shared spins 0, rounds 4, OS waits 2
RW-excl spins 0, rounds 0, OS waits 0
RW-sx spins 0, rounds 0, OS waits 0
Spin rounds per wait: 4.00 RW-shared, 0.00 RW-excl, 0.00 RW-sx
------------
TRANSACTIONS
------------
Trx id counter 12586242
Purge done for trx's n:o < 0 undo n:o < 0 state: running but idle
History list length 0
LIST OF TRANSACTIONS FOR EACH SESSION:
---TRANSACTION 422148342613808, not started
0 lock struct(s), heap size 1136, 0 row lock(s)
--------
FILE I/O
--------
I/O thread 0 state: waiting for i/o request (insert buffer thread)
I/O thread 1 state: waiting for i/o request (log thread)
I/O thread 2 state: waiting for i/o request (read thread)
I/O thread 3 state: waiting for i/o request (read thread)
I/O thread 4 state: waiting for i/o request (read thread)
I/O thread 5 state: waiting for i/o request (read thread)
I/O thread 6 state: waiting for i/o request (write thread)
I/O thread 7 state: waiting for i/o request (write thread)
I/O thread 8 state: waiting for i/o request (write thread)
I/O thread 9 state: waiting for i/o request (write thread)
Pending normal aio reads: [0, 0, 0, 0] , aio writes: [0, 0, 0, 0] ,
ibuf aio reads:, log i/o's:, sync i/o's:
Pending flushes (fsync) log: 0; buffer pool: 0
864 OS file reads, 53 OS file writes, 7 OS fsyncs
0.00 reads/s, 0 avg bytes/read, 0.00 writes/s, 0.00 fsyncs/s
-------------------------------------
INSERT BUFFER AND ADAPTIVE HASH INDEX
-------------------------------------
Ibuf: size 1, free list len 0, seg size 2, 0 merges
merged operations:
insert 0, delete mark 0, delete 0
discarded operations:
insert 0, delete mark 0, delete 0
Hash table size 34679, node heap has 2 buffer(s)
Hash table size 34679, node heap has 0 buffer(s)
Hash table size 34679, node heap has 0 buffer(s)
Hash table size 34679, node heap has 0 buffer(s)
Hash table size 34679, node heap has 0 buffer(s)
Hash table size 34679, node heap has 0 buffer(s)
Hash table size 34679, node heap has 0 buffer(s)
Hash table size 34679, node heap has 2 buffer(s)
0.00 hash searches/s, 0.00 non-hash searches/s
---
LOG
---
Log sequence number 3485478589
Log flushed up to 3485478589
Pages flushed up to 3485478589
Last checkpoint at 3485478580
0 pending log flushes, 0 pending chkp writes
10 log i/o's done, 0.00 log i/o's/second
----------------------
BUFFER POOL AND MEMORY
----------------------
Total large memory allocated 137428992
Dictionary memory allocated 137933
Buffer pool size 8192
Free buffers 7323
Database pages 865
Old database pages 339
Modified db pages 0
Pending reads 0
Pending writes: LRU 0, flush list 0, single page 0
Pages made young 0, not young 0
0.00 youngs/s, 0.00 non-youngs/s
Pages read 831, created 34, written 36
0.00 reads/s, 0.00 creates/s, 0.00 writes/s
No buffer pool page gets since the last printout
Pages read ahead 0.00/s, evicted without access 0.00/s, Random read ahead 0.00/s
LRU len: 865, unzip_LRU len: 0
I/O sum[0]:cur[0], unzip sum[0]:cur[0]
--------------
ROW OPERATIONS
--------------
0 queries inside InnoDB, 0 queries in queue
0 read views open inside InnoDB
Process ID=5986, Main thread ID=13155885056, state: sleeping
Number of rows inserted 0, updated 0, deleted 0, read 8
0.00 inserts/s, 0.00 updates/s, 0.00 deletes/s, 0.00 reads/s
----------------------------
END OF INNODB MONITOR OUTPUT
============================
1 row in set (0.00 sec)
-- 开启后：
mysql> select * from INFORMATION_SCHEMA.INNODB_METRICS WHERE NAME like '%index_page_merge%';
+-----------------------------+-----------+-------+-----------+-----------+-----------+-------------+-----------------+-----------------+-----------------+---------------------+---------------+--------------+------------+---------+---------+----------------------------------------+
| NAME | SUBSYSTEM | COUNT | MAX_COUNT | MIN_COUNT | AVG_COUNT | COUNT_RESET | MAX_COUNT_RESET | MIN_COUNT_RESET | AVG_COUNT_RESET | TIME_ENABLED | TIME_DISABLED | TIME_ELAPSED | TIME_RESET | STATUS | TYPE | COMMENT |
+-----------------------------+-----------+-------+-----------+-----------+-----------+-------------+-----------------+-----------------+-----------------+---------------------+---------------+--------------+------------+---------+---------+----------------------------------------+
| index_page_merge_attempts | index | 0 | NULL | NULL | 0 | 0 | NULL | NULL | NULL | 2025-06-13 09:38:40 | NULL | 400 | NULL | enabled | counter | Number of index page merge attempts |
| index_page_merge_successful | index | 0 | NULL | NULL | 0 | 0 | NULL | NULL | NULL | 2025-06-13 09:38:51 | NULL | 389 | NULL | enabled | counter | Number of successful index page merges |
+-----------------------------+-----------+-------+-----------+-----------+-----------+-------------+-----------------+-----------------+-----------------+---------------------+---------------+--------------+------------+---------+---------+----------------------------------------+
2 rows in set (0.00 sec)
mysql> show engine innodb status\G
*************************** 1. row ***************************
Type: InnoDB
Name:
Status:
=====================================
2025-06-13 09:45:32 0x3107d5000 INNODB MONITOR OUTPUT
=====================================
Per second averages calculated from the last 56 seconds
-----------------
BACKGROUND THREAD
-----------------
srv_master_thread loops: 1 srv_active, 0 srv_shutdown, 505445 srv_idle
srv_master_thread log flush and writes: 505424
----------
SEMAPHORES
----------
OS WAIT ARRAY INFO: reservation count 12
OS WAIT ARRAY INFO: signal count 10
RW-shared spins 0, rounds 4, OS waits 2
RW-excl spins 0, rounds 0, OS waits 0
RW-sx spins 0, rounds 0, OS waits 0
Spin rounds per wait: 4.00 RW-shared, 0.00 RW-excl, 0.00 RW-sx
------------
TRANSACTIONS
------------
Trx id counter 12586242
Purge done for trx's n:o < 0 undo n:o < 0 state: running but idle
History list length 0
LIST OF TRANSACTIONS FOR EACH SESSION:
---TRANSACTION 422148342613808, not started
0 lock struct(s), heap size 1136, 0 row lock(s)
--------
FILE I/O
--------
I/O thread 0 state: waiting for i/o request (insert buffer thread)
I/O thread 1 state: waiting for i/o request (log thread)
I/O thread 2 state: waiting for i/o request (read thread)
I/O thread 3 state: waiting for i/o request (read thread)
I/O thread 4 state: waiting for i/o request (read thread)
I/O thread 5 state: waiting for i/o request (read thread)
I/O thread 6 state: waiting for i/o request (write thread)
I/O thread 7 state: waiting for i/o request (write thread)
I/O thread 8 state: waiting for i/o request (write thread)
I/O thread 9 state: waiting for i/o request (write thread)
Pending normal aio reads: [0, 0, 0, 0] , aio writes: [0, 0, 0, 0] ,
ibuf aio reads:, log i/o's:, sync i/o's:
Pending flushes (fsync) log: 0; buffer pool: 0
864 OS file reads, 53 OS file writes, 7 OS fsyncs
0.00 reads/s, 0 avg bytes/read, 0.00 writes/s, 0.00 fsyncs/s
-------------------------------------
INSERT BUFFER AND ADAPTIVE HASH INDEX
-------------------------------------
Ibuf: size 1, free list len 0, seg size 2, 0 merges
merged operations:
insert 0, delete mark 0, delete 0
discarded operations:
insert 0, delete mark 0, delete 0
Hash table size 34679, node heap has 2 buffer(s)
Hash table size 34679, node heap has 0 buffer(s)
Hash table size 34679, node heap has 0 buffer(s)
Hash table size 34679, node heap has 0 buffer(s)
Hash table size 34679, node heap has 0 buffer(s)
Hash table size 34679, node heap has 0 buffer(s)
Hash table size 34679, node heap has 0 buffer(s)
Hash table size 34679, node heap has 2 buffer(s)
0.00 hash searches/s, 0.00 non-hash searches/s
---
LOG
---
Log sequence number 3485478589
Log flushed up to 3485478589
Pages flushed up to 3485478589
Last checkpoint at 3485478580
0 pending log flushes, 0 pending chkp writes
10 log i/o's done, 0.00 log i/o's/second
----------------------
BUFFER POOL AND MEMORY
----------------------
Total large memory allocated 137428992
Dictionary memory allocated 137933
Buffer pool size 8192
Free buffers 7323
Database pages 865
Old database pages 339
Modified db pages 0
Pending reads 0
Pending writes: LRU 0, flush list 0, single page 0
Pages made young 0, not young 0
0.00 youngs/s, 0.00 non-youngs/s
Pages read 831, created 34, written 36
0.00 reads/s, 0.00 creates/s, 0.00 writes/s
No buffer pool page gets since the last printout
Pages read ahead 0.00/s, evicted without access 0.00/s, Random read ahead 0.00/s
LRU len: 865, unzip_LRU len: 0
I/O sum[0]:cur[0], unzip sum[0]:cur[0]
--------------
ROW OPERATIONS
--------------
0 queries inside InnoDB, 0 queries in queue
0 read views open inside InnoDB
Process ID=5986, Main thread ID=13155885056, state: sleeping
Number of rows inserted 0, updated 0, deleted 0, read 8
0.00 inserts/s, 0.00 updates/s, 0.00 deletes/s, 0.00 reads/s
----------------------------
END OF INNODB MONITOR OUTPUT
============================
1 row in set (0.00 sec)3. INFORMATION_SCHEMA.INNODB_METRICS表说明（以MySQL 8.4版本为例），不同版本请查看INNODB_METRICS表
mysql> SELECT name, subsystem, status FROM INFORMATION_SCHEMA.INNODB_METRICS ORDER BY NAME;
+---------------------------------------------+---------------------+----------+
| name | subsystem | status |
+---------------------------------------------+---------------------+----------+
| adaptive_hash_pages_added | adaptive_hash_index | disabled |
| adaptive_hash_pages_removed | adaptive_hash_index | disabled |
| adaptive_hash_rows_added | adaptive_hash_index | disabled |
| adaptive_hash_rows_deleted_no_hash_entry | adaptive_hash_index | disabled |
| adaptive_hash_rows_removed | adaptive_hash_index | disabled |
| adaptive_hash_rows_updated | adaptive_hash_index | disabled |
| adaptive_hash_searches | adaptive_hash_index | enabled |
| adaptive_hash_searches_btree | adaptive_hash_index | enabled |
| buffer_data_reads | buffer | enabled |
| buffer_data_written | buffer | enabled |
| buffer_flush_adaptive | buffer | disabled |
| buffer_flush_adaptive_avg_pass | buffer | disabled |
| buffer_flush_adaptive_avg_time_est | buffer | disabled |
| buffer_flush_adaptive_avg_time_slot | buffer | disabled |
| buffer_flush_adaptive_avg_time_thread | buffer | disabled |
| buffer_flush_adaptive_pages | buffer | disabled |
| buffer_flush_adaptive_total_pages | buffer | disabled |
| buffer_flush_avg_page_rate | buffer | disabled |
| buffer_flush_avg_pass | buffer | disabled |
| buffer_flush_avg_time | buffer | disabled |
| buffer_flush_background | buffer | disabled |
| buffer_flush_background_pages | buffer | disabled |
| buffer_flush_background_total_pages | buffer | disabled |
| buffer_flush_batches | buffer | disabled |
| buffer_flush_batch_num_scan | buffer | disabled |
| buffer_flush_batch_pages | buffer | disabled |
| buffer_flush_batch_scanned | buffer | disabled |
| buffer_flush_batch_scanned_per_call | buffer | disabled |
| buffer_flush_batch_total_pages | buffer | disabled |
| buffer_flush_lsn_avg_rate | buffer | disabled |
| buffer_flush_neighbor | buffer | disabled |
| buffer_flush_neighbor_pages | buffer | disabled |
| buffer_flush_neighbor_total_pages | buffer | disabled |
| buffer_flush_n_to_flush_by_age | buffer | disabled |
| buffer_flush_n_to_flush_by_dirty_page | buffer | disabled |
| buffer_flush_n_to_flush_requested | buffer | disabled |
| buffer_flush_pct_for_dirty | buffer | disabled |
| buffer_flush_pct_for_lsn | buffer | disabled |
| buffer_flush_sync | buffer | disabled |
| buffer_flush_sync_pages | buffer | disabled |
| buffer_flush_sync_total_pages | buffer | disabled |
| buffer_flush_sync_waits | buffer | disabled |
| buffer_LRU_batches_evict | buffer | disabled |
| buffer_LRU_batches_flush | buffer | disabled |
| buffer_LRU_batch_evict_pages | buffer | disabled |
| buffer_LRU_batch_evict_total_pages | buffer | disabled |
| buffer_LRU_batch_flush_avg_pass | buffer | disabled |
| buffer_LRU_batch_flush_avg_time_est | buffer | disabled |
| buffer_LRU_batch_flush_avg_time_slot | buffer | disabled |
| buffer_LRU_batch_flush_avg_time_thread | buffer | disabled |
| buffer_LRU_batch_flush_pages | buffer | disabled |
| buffer_LRU_batch_flush_total_pages | buffer | disabled |
| buffer_LRU_batch_num_scan | buffer | disabled |
| buffer_LRU_batch_scanned | buffer | disabled |
| buffer_LRU_batch_scanned_per_call | buffer | disabled |
| buffer_LRU_get_free_loops | buffer | disabled |
| buffer_LRU_get_free_search | Buffer | disabled |
| buffer_LRU_get_free_waits | buffer | disabled |
| buffer_LRU_search_num_scan | buffer | disabled |
| buffer_LRU_search_scanned | buffer | disabled |
| buffer_LRU_search_scanned_per_call | buffer | disabled |
| buffer_LRU_single_flush_failure_count | Buffer | disabled |
| buffer_LRU_single_flush_num_scan | buffer | disabled |
| buffer_LRU_single_flush_scanned | buffer | disabled |
| buffer_LRU_single_flush_scanned_per_call | buffer | disabled |
| buffer_LRU_unzip_search_num_scan | buffer | disabled |
| buffer_LRU_unzip_search_scanned | buffer | disabled |
| buffer_LRU_unzip_search_scanned_per_call | buffer | disabled |
| buffer_pages_created | buffer | enabled |
| buffer_pages_read | buffer | enabled |
| buffer_pages_written | buffer | enabled |
| buffer_page_read_blob | buffer_page_io | disabled |
| buffer_page_read_fsp_hdr | buffer_page_io | disabled |
| buffer_page_read_ibuf_bitmap | buffer_page_io | disabled |
| buffer_page_read_ibuf_free_list | buffer_page_io | disabled |
| buffer_page_read_index_ibuf_leaf | buffer_page_io | disabled |
| buffer_page_read_index_ibuf_non_leaf | buffer_page_io | disabled |
| buffer_page_read_index_inode | buffer_page_io | disabled |
| buffer_page_read_index_leaf | buffer_page_io | disabled |
| buffer_page_read_index_non_leaf | buffer_page_io | disabled |
| buffer_page_read_other | buffer_page_io | disabled |
| buffer_page_read_rseg_array | buffer_page_io | disabled |
| buffer_page_read_system_page | buffer_page_io | disabled |
| buffer_page_read_trx_system | buffer_page_io | disabled |
| buffer_page_read_undo_log | buffer_page_io | disabled |
| buffer_page_read_xdes | buffer_page_io | disabled |
| buffer_page_read_zblob | buffer_page_io | disabled |
| buffer_page_read_zblob2 | buffer_page_io | disabled |
| buffer_page_written_blob | buffer_page_io | disabled |
| buffer_page_written_fsp_hdr | buffer_page_io | disabled |
| buffer_page_written_ibuf_bitmap | buffer_page_io | disabled |
| buffer_page_written_ibuf_free_list | buffer_page_io | disabled |
| buffer_page_written_index_ibuf_leaf | buffer_page_io | disabled |
| buffer_page_written_index_ibuf_non_leaf | buffer_page_io | disabled |
| buffer_page_written_index_inode | buffer_page_io | disabled |
| buffer_page_written_index_leaf | buffer_page_io | disabled |
| buffer_page_written_index_non_leaf | buffer_page_io | disabled |
| buffer_page_written_on_log_no_waits | buffer_page_io | disabled |
| buffer_page_written_on_log_waits | buffer_page_io | disabled |
| buffer_page_written_on_log_wait_loops | buffer_page_io | disabled |
| buffer_page_written_other | buffer_page_io | disabled |
| buffer_page_written_rseg_array | buffer_page_io | disabled |
| buffer_page_written_system_page | buffer_page_io | disabled |
| buffer_page_written_trx_system | buffer_page_io | disabled |
| buffer_page_written_undo_log | buffer_page_io | disabled |
| buffer_page_written_xdes | buffer_page_io | disabled |
| buffer_page_written_zblob | buffer_page_io | disabled |
| buffer_page_written_zblob2 | buffer_page_io | disabled |
| buffer_pool_bytes_data | buffer | enabled |
| buffer_pool_bytes_dirty | buffer | enabled |
| buffer_pool_pages_data | buffer | enabled |
| buffer_pool_pages_dirty | buffer | enabled |
| buffer_pool_pages_free | buffer | enabled |
| buffer_pool_pages_misc | buffer | enabled |
| buffer_pool_pages_total | buffer | enabled |
| buffer_pool_reads | buffer | enabled |
| buffer_pool_read_ahead | buffer | enabled |
| buffer_pool_read_ahead_evicted | buffer | enabled |
| buffer_pool_read_requests | buffer | enabled |
| buffer_pool_size | server | enabled |
| buffer_pool_wait_free | buffer | enabled |
| buffer_pool_write_requests | buffer | enabled |
| compression_pad_decrements | compression | disabled |
| compression_pad_increments | compression | disabled |
| compress_pages_compressed | compression | disabled |
| compress_pages_decompressed | compression | disabled |
| cpu_n | cpu | disabled |
| cpu_stime_abs | cpu | disabled |
| cpu_stime_pct | cpu | disabled |
| cpu_utime_abs | cpu | disabled |
| cpu_utime_pct | cpu | disabled |
| dblwr_async_requests | dblwr | disabled |
| dblwr_flush_requests | dblwr | disabled |
| dblwr_flush_wait_events | dblwr | disabled |
| dblwr_sync_requests | dblwr | disabled |
| ddl_background_drop_tables | ddl | disabled |
| ddl_log_file_alter_table | ddl | disabled |
| ddl_online_create_index | ddl | disabled |
| ddl_pending_alter_table | ddl | disabled |
| ddl_sort_file_alter_table | ddl | disabled |
| dml_deletes | dml | enabled |
| dml_inserts | dml | enabled |
| dml_reads | dml | disabled |
| dml_system_deletes | dml | enabled |
| dml_system_inserts | dml | enabled |
| dml_system_reads | dml | enabled |
| dml_system_updates | dml | enabled |
| dml_updates | dml | enabled |
| file_num_open_files | file_system | enabled |
| ibuf_merges | change_buffer | enabled |
| ibuf_merges_delete | change_buffer | enabled |
| ibuf_merges_delete_mark | change_buffer | enabled |
| ibuf_merges_discard_delete | change_buffer | enabled |
| ibuf_merges_discard_delete_mark | change_buffer | enabled |
| ibuf_merges_discard_insert | change_buffer | enabled |
| ibuf_merges_insert | change_buffer | enabled |
| ibuf_size | change_buffer | enabled |
| icp_attempts | icp | disabled |
| icp_match | icp | disabled |
| icp_no_match | icp | disabled |
| icp_out_of_range | icp | disabled |
| index_page_discards | index | disabled |
| index_page_merge_attempts | index | disabled |
| index_page_merge_successful | index | disabled |
| index_page_reorg_attempts | index | disabled |
| index_page_reorg_successful | index | disabled |
| index_page_splits | index | disabled |
| innodb_activity_count | server | enabled |
| innodb_background_drop_table_usec | server | disabled |
| innodb_dblwr_pages_written | server | enabled |
| innodb_dblwr_writes | server | enabled |
| innodb_dict_lru_count | server | disabled |
| innodb_dict_lru_usec | server | disabled |
| innodb_ibuf_merge_usec | server | disabled |
| innodb_master_active_loops | server | disabled |
| innodb_master_idle_loops | server | disabled |
| innodb_master_purge_usec | server | disabled |
| innodb_master_thread_sleeps | server | disabled |
| innodb_mem_validate_usec | server | disabled |
| innodb_page_size | server | enabled |
| innodb_rwlock_sx_os_waits | server | enabled |
| innodb_rwlock_sx_spin_rounds | server | enabled |
| innodb_rwlock_sx_spin_waits | server | enabled |
| innodb_rwlock_s_os_waits | server | enabled |
| innodb_rwlock_s_spin_rounds | server | enabled |
| innodb_rwlock_s_spin_waits | server | enabled |
| innodb_rwlock_x_os_waits | server | enabled |
| innodb_rwlock_x_spin_rounds | server | enabled |
| innodb_rwlock_x_spin_waits | server | enabled |
| lock_deadlocks | lock | enabled |
| lock_deadlock_false_positives | lock | enabled |
| lock_deadlock_rounds | lock | enabled |
| lock_rec_grant_attempts | lock | enabled |
| lock_rec_locks | lock | disabled |
| lock_rec_lock_created | lock | disabled |
| lock_rec_lock_removed | lock | disabled |
| lock_rec_lock_requests | lock | disabled |
| lock_rec_lock_waits | lock | disabled |
| lock_rec_release_attempts | lock | enabled |
| lock_row_lock_current_waits | lock | enabled |
| lock_row_lock_time | lock | enabled |
| lock_row_lock_time_avg | lock | enabled |
| lock_row_lock_time_max | lock | enabled |
| lock_row_lock_waits | lock | enabled |
| lock_schedule_refreshes | lock | enabled |
| lock_table_locks | lock | disabled |
| lock_table_lock_created | lock | disabled |
| lock_table_lock_removed | lock | disabled |
| lock_table_lock_waits | lock | disabled |
| lock_threads_waiting | lock | enabled |
| lock_timeouts | lock | enabled |
| log_checkpoints | log | disabled |
| log_concurrency_margin | log | disabled |
| log_flusher_no_waits | log | disabled |
| log_flusher_waits | log | disabled |
| log_flusher_wait_loops | log | disabled |
| log_flush_avg_time | log | disabled |
| log_flush_lsn_avg_rate | log | disabled |
| log_flush_max_time | log | disabled |
| log_flush_notifier_no_waits | log | disabled |
| log_flush_notifier_waits | log | disabled |
| log_flush_notifier_wait_loops | log | disabled |
| log_flush_total_time | log | disabled |
| log_free_space | log | disabled |
| log_full_block_writes | log | disabled |
| log_lsn_archived | log | disabled |
| log_lsn_buf_dirty_pages_added | log | disabled |
| log_lsn_buf_pool_oldest_approx | log | disabled |
| log_lsn_buf_pool_oldest_lwm | log | disabled |
| log_lsn_checkpoint_age | log | disabled |
| log_lsn_current | log | disabled |
| log_lsn_last_checkpoint | log | disabled |
| log_lsn_last_flush | log | disabled |
| log_max_modified_age_async | log | disabled |
| log_max_modified_age_sync | log | disabled |
| log_next_file | log | disabled |
| log_on_buffer_space_no_waits | log | disabled |
| log_on_buffer_space_waits | log | disabled |
| log_on_buffer_space_wait_loops | log | disabled |
| log_on_file_space_no_waits | log | disabled |
| log_on_file_space_waits | log | disabled |
| log_on_file_space_wait_loops | log | disabled |
| log_on_flush_no_waits | log | disabled |
| log_on_flush_waits | log | disabled |
| log_on_flush_wait_loops | log | disabled |
| log_on_recent_closed_wait_loops | log | disabled |
| log_on_recent_written_wait_loops | log | disabled |
| log_on_write_no_waits | log | disabled |
| log_on_write_waits | log | disabled |
| log_on_write_wait_loops | log | disabled |
| log_padded | log | disabled |
| log_partial_block_writes | log | disabled |
| log_waits | log | enabled |
| log_writer_no_waits | log | disabled |
| log_writer_on_archiver_waits | log | disabled |
| log_writer_on_file_space_waits | log | disabled |
| log_writer_waits | log | disabled |
| log_writer_wait_loops | log | disabled |
| log_writes | log | enabled |
| log_write_notifier_no_waits | log | disabled |
| log_write_notifier_waits | log | disabled |
| log_write_notifier_wait_loops | log | disabled |
| log_write_requests | log | enabled |
| log_write_to_file_requests_interval | log | disabled |
| metadata_table_handles_closed | metadata | disabled |
| metadata_table_handles_opened | metadata | disabled |
| metadata_table_reference_count | metadata | disabled |
| module_cpu | cpu | disabled |
| module_dblwr | dblwr | disabled |
| module_page_track | page_track | disabled |
| os_data_fsyncs | os | enabled |
| os_data_reads | os | enabled |
| os_data_writes | os | enabled |
| os_log_bytes_written | os | enabled |
| os_log_fsyncs | os | enabled |
| os_log_pending_fsyncs | os | enabled |
| os_log_pending_writes | os | enabled |
| os_pending_reads | os | disabled |
| os_pending_writes | os | disabled |
| page_track_checkpoint_partial_flush_request | page_track | disabled |
| page_track_full_block_writes | page_track | disabled |
| page_track_partial_block_writes | page_track | disabled |
| page_track_resets | page_track | disabled |
| purge_del_mark_records | purge | disabled |
| purge_dml_delay_usec | purge | disabled |
| purge_invoked | purge | disabled |
| purge_resume_count | purge | disabled |
| purge_stop_count | purge | disabled |
| purge_truncate_history_count | purge | disabled |
| purge_truncate_history_usec | purge | disabled |
| purge_undo_log_pages | purge | disabled |
| purge_upd_exist_or_extern_records | purge | disabled |
| sampled_pages_read | sampling | disabled |
| sampled_pages_skipped | sampling | disabled |
| trx_active_transactions | transaction | disabled |
| trx_allocations | transaction | disabled |
| trx_commits_insert_update | transaction | disabled |
| trx_nl_ro_commits | transaction | disabled |
| trx_on_log_no_waits | transaction | disabled |
| trx_on_log_waits | transaction | disabled |
| trx_on_log_wait_loops | transaction | disabled |
| trx_rollbacks | transaction | disabled |
| trx_rollbacks_savepoint | transaction | disabled |
| trx_rollback_active | transaction | disabled |
| trx_ro_commits | transaction | disabled |
| trx_rseg_current_size | transaction | disabled |
| trx_rseg_history_len | transaction | enabled |
| trx_rw_commits | transaction | disabled |
| trx_undo_slots_cached | transaction | disabled |
| trx_undo_slots_used | transaction | disabled |
| undo_truncate_count | undo | disabled |
| undo_truncate_done_logging_count | undo | disabled |
| undo_truncate_start_logging_count | undo | disabled |
| undo_truncate_usec | undo | disabled |
+---------------------------------------------+---------------------+----------+
314 rows in set (0.00 sec)最后修改时间：2025-06-13 16:51:50
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