Re: Very bad performances on Oracle

On Sun, 14 Feb 1999, Jim DeCicco wrote:
>
> Asside from the redo log sizing, is there anything else that could explain
> the diference in performance? I have an interest in this, as I'm
> experiencing slower than expected update performance in Oracle.

So many things can potentialy cause slow performance for various operations in Oracle, that it is impossible to conjecture without any real information. That is why Oracle gave us ample information on where all the time is going for a particular session.

The v$session_event table breaks down how much time was spent waiting for the various actions that your server process must perform in order to complete. Looking at this view will tell you where all the time went for a particular operation.

The v$session_wait view will tell you what your server proces is waiting for *right now* and also more specific informaion about that wait, like latch, lock, or file information as it pertains to the wait event that your session is sitting on. This is the best way to find out why your session is performing slowly.

The whole instance aggregates these waits across all sessions in the v$system_event view, which will show you how people are spending the most time on your system. It is very important to understand these views, if you are interested in performance in any way.

--
Jeremiah Wilton http://www.wolfenet.com/~jeremiah Received on Sun Feb 14 1999 - 10:26:28 CST