IO history

 


SELECT 
    name AS db_name,
    (SELECT value FROM v$sysstat WHERE name = 'physical reads') AS physical_reads,
    (SELECT value FROM v$sysstat WHERE name = 'physical writes') AS physical_writes,
    (SELECT value FROM v$sysstat WHERE name = 'physical read bytes')/1024/1024 AS read_MB,
    (SELECT value FROM v$sysstat WHERE name = 'physical write bytes')/1024/1024 AS write_MB
FROM v$database;


SELECT
    snap_id,
    dbid,
    instance_number,
    function_name,
    small_read_ios,
    large_write_ios,
    physical_read_bytes / 1024 / 1024 AS read_MB,
    physical_write_bytes / 1024 / 1024 AS write_MB
FROM
    dba_hist_iostat_function
WHERE
    snap_id BETWEEN :start_snap AND :end_snap;


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