From dba_hist_sqlstat you can fetch the sum(cpu_time_delta) order by
parsing_schema_name to see if any specific user is standing out with
respect to the overall cpu time consumption for good day vs bad day. If
it's equally increased for all the users then mostly the issue is outside
the database or perhaps need to see host related things then.
On Wed, Sep 29, 2021 at 6:39 PM Pap <oracle.developer35@xxxxxxxxx> wrote:
Hello Listers, This is an exadata(X3 full rack) machine. One of
the hosts/compute nodes hosting two database nodes with version 19.9.0.0.0
and 11.2.0.4 respectively. We are encountering a situation in which
suddenly the query execution time has been increased by almost ~50% for
many queries in this database without any change in plan and change in data
volume. Checking the host cpu utilization trend, it's almost doubled from
around that exact time when queries ran longer. The waits for those queries
are all DB CPU. Not sure what the cause and what is the effect here. If
something wrong on the host/hardware is impacting queries or something
wrong with the database/queries itself(but then it looks odd that many
queries are running longer which were running fine since the past).
We checked with the infra team regarding any change that went in for that
host but got an answer as NO. And we didn't see any new
queries/functionalities introduced which might cause this sudden spike in
CPU. So I wanted to understand from experts, how can we get to the
bottom of this issue in such a situation?
