Shulou(Shulou.com)05/31 Report--

This article mainly explains "Oracle how to troubleshoot CPU usage is too high," interested friends may wish to have a look. The method introduced in this paper is simple, fast and practical. Let's let Xiaobian take you to learn "Oracle how to troubleshoot CPU usage is too high"!

CPU main functions: processing instructions, executing operations, requesting actions, controlling time, processing data.

Combined with the high CPU usage of database instances, the possible reason is that the database is performing a large number of operations (full table queries, large sorting, etc.).

Since the company does not have DBAs, it can only investigate database problems by itself.

Is there a deadlock?

The following statements are used to query deadlock and unlock:

View Deadlock IDs

SELECTs.username,l.OBJECT_ID,l.SESSION_ID,s.SERIAL#,

l.Oracle_USERNAME,l.OS_USER_NAME,l.PROCESSFROMV$LOCKED_OBJECT

l,V$SESSIONSWHEREl.SESSION_ID=S.SID;

View table name

selectb.owner,b.object_name,a.session_id,a.locked_modefromv$locked_objecta,dba_objectsbwhereb.object_id=a.object_id;

manual closing deadlock

altersystemkillsession'sid,serial#'; where sid=l.session_id

Deadlocks through the query also found some deadlocks, kill CPU did not come down, can only re-investigation.

Using PLSQL to query timed job sessions

PL/SQL queries show that there is no timed JOB execution.

Through Tools-Sessions, it is found that there are many database connections and accesses, but it is difficult to locate the specific sql or table problems.

Therefore, Kill all the sessions, the CPU has been relieved, but the root cause has not been found, and repeated every few minutes.

process summary

There are many reasons for CPU explosion, and there are many ideas. If you encounter the above ideas later, you can accurately locate the problem and optimize it.

At this point, I believe that everyone has a deeper understanding of "Oracle how to troubleshoot CPU usage is too high," so let's actually operate it! Here is the website, more related content can enter the relevant channels for inquiry, pay attention to us, continue to learn!

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.