Re: performance question

Terry Rose wrote:
>
> My company is currently evaluating Oracle for OLTP. On the server side, we have a
> Tricord with 4 Pentium CPU's, 512MB RAM, running Solaris 2.5 and Oracle 7.3. On
> the client side, we're currently using Windows NT 3.51.
>
> My question is about the third phase which updates the data column of 10000 random
> rows. This phase progresses in "bursts". Using a displayed counter, I can see
> several hundred updates...then a pause...several hundred more...a pause...etc.
>
> What is causing the pauses?

I have seen this behavior when the DBWR process cannot keep up. Everything then waits until DBWR flushes the buffer cache. Since you have 4 CPU's, the parameter 'db_writers' in the INIT.ORA file should have a minimum value of 8 (number of CPU'S * 2). Make sure that your rollback segments and redo logs are large enough. Also your redo logs should have MINEXTENTS >= 4.

Additionally, you might try:

  alter table {table_name} parallel 4;

This will enable parallel operations on your table. Received on Fri Jun 21 1996 - 00:00:00 CEST