Unusual amount of archive logs
A limit management system experienced unplanned downtime, due to archive log area filling up. It turned out that within a space of 10 hours, the system was generating 100GB of archive files, and the tape backup simply could not backup the data fast enough.
To check whether this is a normal activity, we can the following query to check pattern for the last 30 days.
select to_char(trunc(first_time),’DD-MON-YYYY’) business_date, count(*) number_of_archive_logs from gv$log_history where first_time >= sysdate-30 group by trunc(first_time) order by trunc(first_time) desc
We can even break down the rate of the generation by hour,
select count(*), cob, hour from (select to_char(trunc(first_time),’DD-MON-YYYY’) cob , to_char(first_time,’HH24′) hour from gv$log_history where first_time >= sysdate-4) group by cob, hour
And based on the result, pinpoint the problematic time period, and cross check with the application log, to see which component run is causing this unusual high amount of archives.