The INNODB_METRICS table provides
      information about InnoDB performance and
      resource-related counters.
    
      INNODB_METRICS table columns are
      shown below. For column descriptions, see
      Section 28.4.21, “The INFORMATION_SCHEMA INNODB_METRICS Table”.
    
mysql> SELECT * FROM INFORMATION_SCHEMA.INNODB_METRICS WHERE NAME="dml_inserts" \G
*************************** 1. row ***************************
           NAME: dml_inserts
      SUBSYSTEM: dml
          COUNT: 46273
      MAX_COUNT: 46273
      MIN_COUNT: NULL
      AVG_COUNT: 492.2659574468085
    COUNT_RESET: 46273
MAX_COUNT_RESET: 46273
MIN_COUNT_RESET: NULL
AVG_COUNT_RESET: NULL
   TIME_ENABLED: 2014-11-28 16:07:53
  TIME_DISABLED: NULL
   TIME_ELAPSED: 94
     TIME_RESET: NULL
         STATUS: enabled
           TYPE: status_counter
        COMMENT: Number of rows inserted
Enabling, Disabling, and Resetting Counters
You can enable, disable, and reset counters using the following variables:
innodb_monitor_enable: Enables counters.SET GLOBAL innodb_monitor_enable = [counter-name|module_name|pattern|all];innodb_monitor_disable: Disables counters.SET GLOBAL innodb_monitor_disable = [counter-name|module_name|pattern|all];innodb_monitor_reset: Resets counter values to zero.SET GLOBAL innodb_monitor_reset = [counter-name|module_name|pattern|all];innodb_monitor_reset_all: Resets all counter values. A counter must be disabled before usinginnodb_monitor_reset_all.SET GLOBAL innodb_monitor_reset_all = [counter-name|module_name|pattern|all];
      Counters and counter modules can also be enabled at startup using
      the MySQL server configuration file. For example, to enable the
      log module,
      metadata_table_handles_opened and
      metadata_table_handles_closed counters, enter
      the following line in the [mysqld] section of
      the MySQL server configuration file.
    
[mysqld]
innodb_monitor_enable = log,metadata_table_handles_opened,metadata_table_handles_closed
      When enabling multiple counters or modules in a configuration
      file, specify the
      innodb_monitor_enable variable
      followed by counter and module names separated by a comma, as
      shown above. Only the
      innodb_monitor_enable variable
      can be used in a configuration file. The
      innodb_monitor_disable and
      innodb_monitor_reset variables
      are supported on the command line only.
Because each counter adds a degree of runtime overhead, use counters conservatively on production servers to diagnose specific issues or monitor specific functionality. A test or development server is recommended for more extensive use of counters.
Counters
      The list of available counters is subject to change. Query the
      Information Schema INNODB_METRICS
      table for counters available in your MySQL server version.
    
      The counters enabled by default correspond to those shown in
      SHOW ENGINE INNODB
      STATUS output. Counters shown in
      SHOW ENGINE INNODB
      STATUS output are always enabled at a system level but
      can be disabled for the
      INNODB_METRICS table. Counter status
      is not persistent. Unless configured otherwise, counters revert to
      their default enabled or disabled status when the server is
      restarted.
    
      If you run programs that would be affected by the addition or
      removal of counters, it is recommended that you review the
      releases notes and query the
      INNODB_METRICS table to identify
      those changes as part of your upgrade process.
    
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)
Counter Modules
      Each counter is associated with a particular module. Module names
      can be used to enable, disable, or reset all counters for a
      particular subsystem. For example, use
      module_dml to enable all counters associated
      with the dml subsystem.
    
mysql> SET GLOBAL innodb_monitor_enable = module_dml;
mysql> SELECT name, subsystem, status FROM INFORMATION_SCHEMA.INNODB_METRICS
       WHERE subsystem ='dml';
+-------------+-----------+---------+
| name        | subsystem | status  |
+-------------+-----------+---------+
| dml_reads   | dml       | enabled |
| dml_inserts | dml       | enabled |
| dml_deletes | dml       | enabled |
| dml_updates | dml       | enabled |
+-------------+-----------+---------+
      Module names can be used with
      innodb_monitor_enable and related
      variables.
    
      Module names and corresponding SUBSYSTEM names
      are listed below.
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)
Example 17.11 Working with INNODB_METRICS Table Counters
        This example demonstrates enabling, disabling, and resetting a
        counter, and querying counter data in the
        INNODB_METRICS table.
Create a simple
InnoDBtable:mysql> USE test; Database changed mysql> CREATE TABLE t1 (c1 INT) ENGINE=INNODB; Query OK, 0 rows affected (0.02 sec)Enable the
dml_insertscounter.mysql> SET GLOBAL innodb_monitor_enable = dml_inserts; Query OK, 0 rows affected (0.01 sec)A description of the
dml_insertscounter can be found in theCOMMENTcolumn of theINNODB_METRICStable:mysql> SELECT NAME, COMMENT FROM INFORMATION_SCHEMA.INNODB_METRICS WHERE NAME="dml_inserts"; +-------------+-------------------------+ | NAME | COMMENT | +-------------+-------------------------+ | dml_inserts | Number of rows inserted | +-------------+-------------------------+Query the
INNODB_METRICStable for thedml_insertscounter data. Because no DML operations have been performed, the counter values are zero or NULL. TheTIME_ENABLEDandTIME_ELAPSEDvalues indicate when the counter was last enabled and how many seconds have elapsed since that time.mysql> SELECT * FROM INFORMATION_SCHEMA.INNODB_METRICS WHERE NAME="dml_inserts" \G *************************** 1. row *************************** NAME: dml_inserts SUBSYSTEM: dml COUNT: 0 MAX_COUNT: 0 MIN_COUNT: NULL AVG_COUNT: 0 COUNT_RESET: 0 MAX_COUNT_RESET: 0 MIN_COUNT_RESET: NULL AVG_COUNT_RESET: NULL TIME_ENABLED: 2014-12-04 14:18:28 TIME_DISABLED: NULL TIME_ELAPSED: 28 TIME_RESET: NULL STATUS: enabled TYPE: status_counter COMMENT: Number of rows insertedInsert three rows of data into the table.
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)Query the
INNODB_METRICStable again for thedml_insertscounter data. A number of counter values have now incremented includingCOUNT,MAX_COUNT,AVG_COUNT, andCOUNT_RESET. Refer to theINNODB_METRICStable definition for descriptions of these values.mysql> SELECT * FROM INFORMATION_SCHEMA.INNODB_METRICS WHERE NAME="dml_inserts"\G *************************** 1. row *************************** NAME: dml_inserts SUBSYSTEM: dml COUNT: 3 MAX_COUNT: 3 MIN_COUNT: NULL AVG_COUNT: 0.046153846153846156 COUNT_RESET: 3 MAX_COUNT_RESET: 3 MIN_COUNT_RESET: NULL AVG_COUNT_RESET: NULL TIME_ENABLED: 2014-12-04 14:18:28 TIME_DISABLED: NULL TIME_ELAPSED: 65 TIME_RESET: NULL STATUS: enabled TYPE: status_counter COMMENT: Number of rows insertedReset the
dml_insertscounter and query theINNODB_METRICStable again for thedml_insertscounter data. The%_RESETvalues that were reported previously, such asCOUNT_RESETandMAX_RESET, are set back to zero. Values such asCOUNT,MAX_COUNT, andAVG_COUNT, which cumulatively collect data from the time the counter is enabled, are unaffected by the reset.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_inserts SUBSYSTEM: dml COUNT: 3 MAX_COUNT: 3 MIN_COUNT: NULL AVG_COUNT: 0.03529411764705882 COUNT_RESET: 0 MAX_COUNT_RESET: 0 MIN_COUNT_RESET: NULL AVG_COUNT_RESET: 0 TIME_ENABLED: 2014-12-04 14:18:28 TIME_DISABLED: NULL TIME_ELAPSED: 85 TIME_RESET: 2014-12-04 14:19:44 STATUS: enabled TYPE: status_counter COMMENT: Number of rows insertedTo reset all counter values, you must first disable the counter. Disabling the counter sets the
STATUSvalue todisabled.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_inserts SUBSYSTEM: dml COUNT: 3 MAX_COUNT: 3 MIN_COUNT: NULL AVG_COUNT: 0.030612244897959183 COUNT_RESET: 0 MAX_COUNT_RESET: 0 MIN_COUNT_RESET: NULL AVG_COUNT_RESET: 0 TIME_ENABLED: 2014-12-04 14:18:28 TIME_DISABLED: 2014-12-04 14:20:06 TIME_ELAPSED: 98 TIME_RESET: NULL STATUS: disabled TYPE: status_counter COMMENT: Number of rows insertedNoteWildcard match is supported for counter and module names. For example, instead of specifying the full
dml_insertscounter name, you can specifydml_i%. You can also enable, disable, or reset multiple counters or modules at once using a wildcard match. For example, specifydml_%to enable, disable, or reset all counters that begin withdml_.After the counter is disabled, you can reset all counter values using the
innodb_monitor_reset_alloption. All values are set to zero or 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_inserts SUBSYSTEM: dml 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: status_counter COMMENT: Number of rows inserted