Oracle execute slowly, every morning the same SQL, 0.5 s return at ordinary times, need more than 10 s in the morning,
See IO, the CPU is not high,
To check the database lock is no exception,
See who runs AWR reports, ability problems also look not to come out, which under the guidance of attention?

CodePudding user response:

1, because the big probability problem caused by the system load in the morning, don't know what do you think the building Lord at the time of resources, stick down the best state of system resources;
2, since the building Lord who runs AWR reports, if convenient, it is best to pass the SQL run slow time who runs AWR report,

CodePudding user response:

Cache and indexing problem, how long do you clear the cache try at ordinary times, after clear the cache or 10 seconds, is the problem of index

CodePudding user response:

1, slow on morning who runs AWR look;
2, find slow SQL SQL_ID, use dbms_xplan. Display_cursor or SQL execution plan, do not rule out because of some features, such as cardinality feedback in execution plans change,

CodePudding user response:

If execution plan confirmed that there is no problem, you need to monitor global analysis, at the time whether performance pressure? If there is a phenomenon such as lock or this table