Improved Mysql plugin

plugins/inputs/mysql/README.md

@@ -0,0 +1,170 @@
+# MySQL Input plugin
+
+This plugin gathers the statistic data from MySQL server
+
+* Global statuses
+* Global variables
+* Slave statuses
+* Binlog size
+* Process list
+* Info schema auto increment columns
+* Table I/O waits
+* Index I/O waits
+* Perf Schema table lock waits
+* Perf Schema event waits
+* Perf Schema events statements
+* File events statistics
+* Table schema statistics
+
+## Configuration
+
+Example configuration:
+The metrics that requires 
+```
+# specify servers via a url matching:
+#  [username[:password]@][protocol[(address)]]/[?tls=[true|false|skip-verify]]
+#  see https://github.com/go-sql-driver/mysql#dsn-data-source-name
+#  e.g.
+#    root:passwd@tcp(127.0.0.1:3306)/?tls=false
+#    root@tcp(127.0.0.1:3306)/?tls=false
+#
+# If no servers are specified, then localhost is used as the host.
+servers = ["tcp(127.0.0.1:3306)/"]
+# the limits for metrics form perf_events_statements
+perf_events_statements_digest_text_limit  = 120
+perf_events_statements_limit              = 250
+perf_events_statements_time_limit         = 86400
+# if the list is empty, then metrics are gathered from all databasee tables
+table_schema_databases                    = []
+# gather metrics from INFORMATION_SCHEMA.TABLES for databases provided above list
+gather_table_schema                       = false
+# gather thread state counts from INFORMATION_SCHEMA.PROCESSLIST 
+gather_process_list                       = true
+# gather auto_increment columns and max values from information schema
+gather_info_schema_auto_inc               = true
+# gather metrics from SHOW SLAVE STATUS command output
+gather_slave_status                       = true
+# gather metrics from SHOW BINARY LOGS command output
+gather_binary_logs                        = false
+# gather metrics from PERFORMANCE_SCHEMA.TABLE_IO_WAITS_SUMMART_BY_TABLE
+gather_table_io_waits                     = false
+# gather metrics from PERFORMANCE_SCHEMA.TABLE_IO_WAITS_SUMMART_BY_INDEX_USAGE
+gather_index_io_waits                     = false
+# gather metrics from PERFORMANCE_SCHEMA.FILE_SUMMARY_BY_EVENT_NAME 
+gather_file_events_stats                  = false
+# gather metrics from PERFORMANCE_SCHEMA.EVENTS_STATEMENTS_SUMMARY_BY_DIGEST
+gather_perf_events_statements             = false
+# Some queries we may want to run less often (such as SHOW GLOBAL VARIABLES)
+interval_slow                   = "30m"
+```
+
+## Measurements & Fields
+* Global statuses - all numeric and boolean values of `SHOW GLOBAL STATUSES`
+* Global variables - all numeric and boolean values of `SHOW GLOBAL VARIABLES`
+* Slave status - metrics from `SHOW SLAVE STATUS` the metrics are gathered when the single-source replication is on. If the multi-source replication is set, then everything works differently, this metric does not work with multi-source replication.
+    * slave_[column name]()
+* Binary logs - all metrics including size and count of all binary files. Requires to be turned on in configuration.
+    * binary_size_bytes(int, number)
+    * binary_files_count(int, number)
+* Process list - connection metrics from processlist for each user. It has the following tags
+    * connections(int, number)
+* Perf Table IO waits - total count and time of I/O waits event for each table and process. It has following fields:
+    * table_io_waits_total_fetch(float, number)
+    * table_io_waits_total_insert(float, number)
+    * table_io_waits_total_update(float, number)
+    * table_io_waits_total_delete(float, number)
+    * table_io_waits_seconds_total_fetch(float, milliseconds)
+    * table_io_waits_seconds_total_insert(float, milliseconds)
+    * table_io_waits_seconds_total_update(float, milliseconds)
+    * table_io_waits_seconds_total_delete(float, milliseconds)
+* Perf index IO waits - total count and time of I/O waits event for each index and process. It has following fields:
+    * index_io_waits_total_fetch(float, number)
+    * index_io_waits_seconds_total_fetch(float, milliseconds)
+    * index_io_waits_total_insert(float, number)
+    * index_io_waits_total_update(float, number)
+    * index_io_waits_total_delete(float, number)
+    * index_io_waits_seconds_total_insert(float, milliseconds)
+    * index_io_waits_seconds_total_update(float, milliseconds)
+    * index_io_waits_seconds_total_delete(float, milliseconds)
+* Info schema autoincrement statuses - autoincrement fields and max values for them. It has following fields:
+    * auto_increment_column(int, number)
+    * auto_increment_column_max(int, number)
+* Perf table lock waits - gathers total number and time for SQL and external lock waits events for each table and operation. It has following fields. The unit of fields varies by the tags.
+    * read_normal(float, number/milliseconds)
+    * read_with_shared_locks(float, number/milliseconds)
+    * read_high_priority(float, number/milliseconds)
+    * read_no_insert(float, number/milliseconds)
+    * write_normal(float, number/milliseconds)
+    * write_allow_write(float, number/milliseconds)
+    * write_concurrent_insert(float, number/milliseconds)
+    * write_delayed(float, number/milliseconds)
+    * write_low_priority(float, number/milliseconds)
+    * read(float, number/milliseconds)
+    * write(float, number/milliseconds)
+* Perf events waits - gathers total time and number of event waits
+    * events_waits_total(float, number)
+    * events_waits_seconds_total(float, milliseconds)
+* Perf file events statuses - gathers file events statuses
+    * file_events_total(float,number)
+    * file_events_seconds_total(float, milliseconds)
+    * file_events_bytes_total(float, bytes)
+* Perf file events statements - gathers attributes of each event
+    * events_statements_total(float, number)
+    * events_statements_seconds_total(float, millieconds)
+    * events_statements_errors_total(float, number)
+    * events_statements_warnings_total(float, number)
+    * events_statements_rows_affected_total(float, number)
+    * events_statements_rows_sent_total(float, number)
+    * events_statements_rows_examined_total(float, number)
+    * events_statements_tmp_tables_total(float, number)
+    * events_statements_tmp_disk_tables_total(float, number)
+    * events_statements_sort_merge_passes_totales(float, number)
+    * events_statements_sort_rows_total(float, number)
+    * events_statements_no_index_used_total(float, number)
+* Table schema - gathers statistics of each schema. It has following measurements
+    * info_schema_table_rows(float, number)
+    * info_schema_table_size_data_length(float, number)
+    * info_schema_table_size_index_length(float, number)
+    * info_schema_table_size_data_free(float, number)
+    * info_schema_table_version(float, number)
+
+## Tags
+* All measurements has following tags
+    * server (the host name from which the metrics are gathered)
+* Process list measurement has following tags
+    * user (username for whom the metrics are gathered)
+* Perf table IO waits measurement has following tags
+    * schema
+    * name (object name for event or process)
+* Perf index IO waits has following tags
+    * schema
+    * name
+    * index
+* Info schema autoincrement statuses has following tags
+    * schema
+    * table
+    * column
+* Perf table lock waits has following tags
+    * schema
+    * table
+    * sql_lock_waits_total(fields including this tag have numeric unit)
+    * external_lock_waits_total(fields including this tag have numeric unit)
+    * sql_lock_waits_seconds_total(fields including this tag have millisecond unit)
+    * external_lock_waits_seconds_total(fields including this tag have millisecond unit)
+* Perf events statements has following tags
+    * event_name
+* Perf file events statuses has following tags
+    * event_name
+    * mode
+* Perf file events statements has following tags
+    * schema
+    * digest
+    * digest_text
+* Table schema has following tags
+    * schema
+    * table
+    * component
+    * type
+    * engine
+    * row_format
+    * create_options