1.介绍

INNODB_METRICS表提供了有关INNODB性能和资源相关计数器的信息。

INNODB_METRICS表列如下所示。

有关列描述，请参阅“INFORMATION_SCHEMA库INNODB_METRICS表”。

【MySQL精通之路】INFORMATION_SCHEMA库-INNODB_METRICS表-CSDN博客

mysql> SELECT * FROM INFORMATION_SCHEMA.INNODB_METRICS WHERE NAME="dml_inserts" \G
*************************** 1. row ***************************NAME: dml_insertsSUBSYSTEM: dmlCOUNT: 46273MAX_COUNT: 46273MIN_COUNT: NULLAVG_COUNT: 492.2659574468085COUNT_RESET: 46273
MAX_COUNT_RESET: 46273
MIN_COUNT_RESET: NULL
AVG_COUNT_RESET: NULLTIME_ENABLED: 2014-11-28 16:07:53TIME_DISABLED: NULLTIME_ELAPSED: 94TIME_RESET: NULLSTATUS: enabledTYPE: status_counterCOMMENT: Number of rows inserted

启用、禁用和重置计数器
您可以使用以下变量启用、禁用和重置计数器：

innodb_monitor_enable: 启用计数

SET GLOBAL innodb_monitor_enable = [counter-name|module_name|pattern|all];

innodb_monitor_disable: 禁用计数

SET GLOBAL innodb_monitor_reset = [counter-name|module_name|pattern|all];

innodb_monitor_reset: 将计数重置为零

SET GLOBAL innodb_monitor_reset = [counter-name|module_name|pattern|all];

innodb_monitor_reset_all：重置所有计数器值。在使用innodb_monitor_reset_all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使用MySQL服务器配置文件启用。

例如：

要启用日志模块metadata_table_handles_opened和metadata_ttable_handles_connected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 = log,metadata_table_handles_opened,metadata_table_handles_closed

在配置文件中启用多个计数器或模块时，请指定innodb_monitor_enable变量，后跟用逗号分隔的计数器和模块名称，如上所示。配置文件中只能使用innodb_monitor_enable变量。innodb_monitor_disable和innodb_monitor _reset变量仅在命令行上受支持。

注意:

因为每个计数器都会增加一定程度的运行时开销，所以在生产服务器上保守地使用计数器来诊断特定问题或监视特定功能。建议使用测试或开发服务器以更广泛地使用计数器。

2.计数器

可用计数器的列表可能会更改。在Information Schema库 INNODB_METRICS表中查询MySQL服务器版本中可用的计数器。

默认启用的计数器对应于SHOW ENGINE INNODB STATUS输出中显示的计数器。

SHOW ENGINE INNODB STATUS输出中显示的计数器始终在系统级别启用，但可以禁用INNODB_METRICS表。

计数器状态不是持久的。

除非另有配置，否则当服务器重新启动时，计数器将恢复到默认的启用或禁用状态。

如果您运行的程序会受到计数器添加或删除的影响，建议您查看发行说明并查询INNODB_METRICS表，以将这些更改标识为升级过程的一部分。

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)

3.计数器模块

每个计数器都与一个特定的模块相关联。模块名称可用于启用、禁用或重置特定子系统的所有计数器。例如，使用module_dml启用与dml子系统关联的所有计数器。

mysql> SET GLOBAL innodb_monitor_enable = module_dml;mysql> SELECT name, subsystem, status FROM INFORMATION_SCHEMA.INNODB_METRICSWHERE subsystem ='dml';
+-------------+-----------+---------+
| name        | subsystem | status  |
+-------------+-----------+---------+
| dml_reads   | dml       | enabled |
| dml_inserts | dml       | enabled |
| dml_deletes | dml       | enabled |
| dml_updates | dml       | enabled |
+-------------+-----------+---------+

模块名称可以与innodb_monitor_enable和相关变量一起使用。

下面列出了模块名称和相应的SUBSYSTEM名称。

module_adaptive_hash (subsystem = adaptive_hash_index)

module_buffer (subsystem = buffer)

module_buffer_page (subsystem = buffer_page_io)

module_compress (subsystem = compression)

module_ddl (subsystem = ddl)

module_dml (subsystem = dml)

module_file (subsystem = file_system)

module_ibuf_system (subsystem = change_buffer)

module_icp (subsystem = icp)

module_index (subsystem = index)

module_innodb (subsystem = innodb)

module_lock (subsystem = lock)

module_log (subsystem = log)

module_metadata (subsystem = metadata)

module_os (subsystem = os)

module_purge (subsystem = purge)

module_trx (subsystem = transaction)

module_undo (subsystem = undo)

4.计数器的使用

示例使用INNODB_METRICS表计数器

此示例演示启用、禁用和重置计数器，以及查询INNODB_METRICS表中的计数器数据。

建表:

mysql> USE test;
Database changedmysql> CREATE TABLE t1 (c1 INT) ENGINE=INNODB;
Query OK, 0 rows affected (0.02 sec)

开启 dml_inserts 计数器.

mysql> SET GLOBAL innodb_monitor_enable = dml_inserts;
Query OK, 0 rows affected (0.01 sec)

可以在INNODB_METRICS表的COMMENT列中找到dml_inserts计数器的描述：

mysql> SELECT NAME, COMMENT FROM INFORMATION_SCHEMA.INNODB_METRICS WHERE NAME="dml_inserts";
+-------------+-------------------------+
| NAME        | COMMENT                 |
+-------------+-------------------------+
| dml_inserts | Number of rows inserted |
+-------------+-------------------------+

查询INNODB_METRICS表中的dml_inserts计数器数据。因为没有执行DML操作，所以计数器值为零或NULL。TIME_ENABLED和TIME_ELAPSED值指示计数器上次启用的时间以及自该时间以来经过的秒数。

mysql>  SELECT * FROM INFORMATION_SCHEMA.INNODB_METRICS WHERE NAME="dml_inserts" \G
*************************** 1. row ***************************NAME: dml_insertsSUBSYSTEM: dmlCOUNT: 0MAX_COUNT: 0MIN_COUNT: NULLAVG_COUNT: 0COUNT_RESET: 0
MAX_COUNT_RESET: 0
MIN_COUNT_RESET: NULL
AVG_COUNT_RESET: NULLTIME_ENABLED: 2014-12-04 14:18:28TIME_DISABLED: NULLTIME_ELAPSED: 28TIME_RESET: NULLSTATUS: enabledTYPE: status_counterCOMMENT: Number of rows inserted

在表中插入三行数据。

mysql> INSERT INTO t1 values(1);
Query OK, 1 row affected (0.00 sec)mysql> INSERT INTO t1 values(2);
Query OK, 1 row affected (0.00 sec)mysql> INSERT INTO t1 values(3);
Query OK, 1 row affected (0.00 sec)

再次查询INNODB_METRICS表中的dml_inserts计数器数据。现在，许多计数器值已递增，包括COUNT、MAX_COUNT、AVG_COUNT和COUNT_RESET。有关这些值的描述，请参阅INNODB_METRICS表定义。

mysql>  SELECT * FROM INFORMATION_SCHEMA.INNODB_METRICS WHERE NAME="dml_inserts"\G
*************************** 1. row ***************************NAME: dml_insertsSUBSYSTEM: dmlCOUNT: 3MAX_COUNT: 3MIN_COUNT: NULLAVG_COUNT: 0.046153846153846156COUNT_RESET: 3
MAX_COUNT_RESET: 3
MIN_COUNT_RESET: NULL
AVG_COUNT_RESET: NULLTIME_ENABLED: 2014-12-04 14:18:28TIME_DISABLED: NULLTIME_ELAPSED: 65TIME_RESET: NULLSTATUS: enabledTYPE: status_counterCOMMENT: Number of rows inserted

重置dml_inserts计数器，并再次查询INNODB_METRICS表中的dml_inserters计数器数据。先前报告的%_RESET值（如COUNT_RESET和MAX_RESET）将设置回零。COUNT、MAX_COUNT和AVG_COUNT等值从计数器启用时开始累积收集数据，不受重置的影响。

mysql> SET GLOBAL innodb_monitor_reset = dml_inserts;
Query OK, 0 rows affected (0.00 sec)mysql> SELECT * FROM INFORMATION_SCHEMA.INNODB_METRICS WHERE NAME="dml_inserts"\G
*************************** 1. row ***************************NAME: dml_insertsSUBSYSTEM: dmlCOUNT: 3MAX_COUNT: 3MIN_COUNT: NULLAVG_COUNT: 0.03529411764705882COUNT_RESET: 0
MAX_COUNT_RESET: 0
MIN_COUNT_RESET: NULL
AVG_COUNT_RESET: 0TIME_ENABLED: 2014-12-04 14:18:28TIME_DISABLED: NULLTIME_ELAPSED: 85TIME_RESET: 2014-12-04 14:19:44STATUS: enabledTYPE: status_counterCOMMENT: Number of rows inserted

要重置所有计数器值，必须首先禁用计数器。禁用计数器会将STATUS值设置为disabled。

mysql> SET GLOBAL innodb_monitor_disable = dml_inserts;
Query OK, 0 rows affected (0.00 sec)mysql> SELECT * FROM INFORMATION_SCHEMA.INNODB_METRICS WHERE NAME="dml_inserts"\G
*************************** 1. row ***************************NAME: dml_insertsSUBSYSTEM: dmlCOUNT: 3MAX_COUNT: 3MIN_COUNT: NULLAVG_COUNT: 0.030612244897959183COUNT_RESET: 0
MAX_COUNT_RESET: 0
MIN_COUNT_RESET: NULL
AVG_COUNT_RESET: 0TIME_ENABLED: 2014-12-04 14:18:28TIME_DISABLED: 2014-12-04 14:20:06TIME_ELAPSED: 98TIME_RESET: NULLSTATUS: disabledTYPE: status_counterCOMMENT: Number of rows inserted

注意：
计数器和模块名称支持通配符匹配。例如，您可以指定dml_i%，而不是指定完整的dml_inserts计数器名称。您还可以使用通配符匹配同时启用、禁用或重置多个计数器或模块。例如，指定dml_%以启用、禁用或重置所有以dml_开头的计数器。

禁用计数器后，可以使用innodb_monitor_reset_all选项重置所有计数器值。所有值都设置为零或NULL。

mysql> SET GLOBAL innodb_monitor_reset_all = dml_inserts;
Query OK, 0 rows affected (0.00 sec)mysql> SELECT * FROM INFORMATION_SCHEMA.INNODB_METRICS WHERE NAME="dml_inserts"\G
*************************** 1. row ***************************NAME: dml_insertsSUBSYSTEM: dmlCOUNT: 0MAX_COUNT: NULLMIN_COUNT: NULLAVG_COUNT: NULLCOUNT_RESET: 0
MAX_COUNT_RESET: NULL
MIN_COUNT_RESET: NULL
AVG_COUNT_RESET: NULLTIME_ENABLED: NULLTIME_DISABLED: NULLTIME_ELAPSED: NULLTIME_RESET: NULLSTATUS: disabledTYPE: status_counterCOMMENT: Number of rows inserted