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Industrial  RDBMS vendors (Oracle, Postgres, MySQL)  collect detailed IO statistics in dimensions such as queries, database objects (tables and indexes), files, sessions, users, event types etc. 

• Oracle

  • v$filestat - This view displays the number of physical reads and writes done and the total number of single-block and multiblock I/Os done at file level

  • v$segment_statistics -  displays information about segment-level statistics.

  • v$sqlarea -  lists statistics on shared SQL area and contains one row per SQL string. It provides statistics on SQL statements that are in memory, parsed, and ready for execution.

  • v$sysstat - displays system statistics. 

  • v$sesstat - displays user session statistics. 

  • AWR - historical statistics.

• PostgreSQL

• • pg_stat_database - Contain one row for each database in the cluster, showing database-wide statistics.

  • pg_statio_all_tables - Contain one row for each table in the current database (including TOAST tables), showing statistics about I/O on that specific table.

  • pg_statio_all_indexes -  Contain one row for each index in the current database, showing statistics about I/O on that specific index.

  • pg_stat_all_indexes - Contain one row for each index in the current database, showing statistics about accesses to that specific index. 

  • pg_stat_all_tables - Contain one row for each table in the current database, showing statistics about accesses to that specific table.

• MySQL

  • table_io_waits_summary_by_table - Table aggregates all table I/O wait events. The grouping is by table.

  • table_io_waits_summary_by_index_usage - Table aggregates all table index I/O wait events. The grouping is by table index.

  • io_global_by_file_by_bytes - These views summarize global I/O consumers to display amount of I/O, grouped by file. 

  • io_global_by_wait_by_bytes -These views summarize global I/O consumers to display amount of I/O and time waiting for I/O, grouped by event. 

  • host_summary_by_file_io - These views summarize file I/O, grouped by host.

  • user_summary_by_file_io - These views summarize file I/O, grouped by user.

  • metrics - This view summarizes MySQL server metrics.

Risks and Assumptions

// Describe project risks, such as API or binary compatibility issues, major protocol changes, etc.

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