5 Replies Latest reply: Oct 3, 2007 11:13 AM by orafad RSS

    top events question

    598168
      Event     Waits     Time(s)     Avg Wait(ms)     % Total Call Time     Wait Class
      CPU time     1,167          86.9     
      db file sequential read     111,047 223      2     16.6     User I/O
      log file sync      77,390 132     2     9.9      Commit
      log file parallel write     78,060     124     2     9.2     System I/O
      db file scattered read     79,233     10     0     0.7     User I/O

      sorry about the formatting.

      From AWR I am seeing a lot of CPU taking most call time %.

      Can anyone explain what this means. I have looked on metalink and there are a number of doc regarding top events in general.

      rgds

      R
        • 1. Re: top events question
          153119
          This is your load profile.
          86 percent of your snapshot interval is devoted to the system using CPU on behalf of the end-users.
          This is quite good!
          db file sequential read: the database is waiting for a block from disk
          db file scattered read: the database is waiting for db_file_multiblock_read_count blocks.
          log file sync: the database is waiting for a commit to complete.

          --
          Sybrand Bakker
          Senior Oracle DBA
          • 2. Re: top events question
            547086
            Hi, you have problems with the IO performance, in the events you can see waits for I/O, you can review the Note:276514.1 into Metalink site.

            Regards.
            • 3. Re: top events question
              orafad
              Hm, to me that profile looks more like an app putting load on the database server... but either way, you can't really tell just by looking at a few context-less numbers.
              • 4. Re: top events question
                598168
                hi,
                Sorry am a bit confused by the replies. Someone says it is good, others say bad.

                There is an application running against the DB.

                I will review the metalink note

                cheers
                R
                • 5. Re: top events question
                  orafad
                  Sorry am a bit confused by the replies. Someone says
                  it is good, others say bad.
                  That was sort of my point. Maybe, for example, the log write is a problem, but unless you have a real, specific performance issue then it's just chasing numbers and a waste of time.