High CPU on Host
From: Pap <oracle.developer35_at_gmail.com>
Date: Wed, 29 Sep 2021 18:38:51 +0530
Message-ID: <CAEjw_fjOBztEwHA4+iTeoKDtjZaJ7SmjFQusVJJY9GR5A3mkMg_at_mail.gmail.com>
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).
Date: Wed, 29 Sep 2021 18:38:51 +0530
Message-ID: <CAEjw_fjOBztEwHA4+iTeoKDtjZaJ7SmjFQusVJJY9GR5A3mkMg_at_mail.gmail.com>
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?
-- http://www.freelists.org/webpage/oracle-lReceived on Wed Sep 29 2021 - 15:08:51 CEST