[20180625]简单计算日志生成率.txt

--//执行前最好做一次日志归档.主要目的了解正常业务时redo的生成率.

--//alter syste archive log current;

SELECT thread#

        ,sequence#         ,first_time         ,next_time         ,blocks * block_size / 1024 / 1024 MB         , (next_time - first_time) * 86400 sec         ,  blocks          * block_size          / 1024          / ( (next_time - first_time) * 86400)             "KB/s"     FROM v$archived_log    WHERE     ( (next_time - first_time) * 86400 >= 1)          AND first_time BETWEEN TRUNC (SYSDATE) - 1 AND  TRUNC (SYSDATE) + 1          AND dest_id = 1 ORDER BY first_time;

--//注:((next_time-first_time)*86400 >=1), 取消一些快速切换的情况,避免存在大的误差.

--//可以根据需要调整.