- reduce the size of the log files. larger files take longer to switch.
- the indication you give is the db is for OLTP...turn archive log off if
it is on, since archive log is needed only when values are being changed.
- are your files on separate logical volumes or separate physical disks?
- are the physical disks where I/O separation is desired also on separate
controller cards? controller contention can be a problem.
- upgrade the controller cards with more buffer cache/memory or get faster
controller cards.
- get faster hard disks (10,000+ rpm SCSI with large cache).
"Reza" <reza_at_digital-dispatch.co.uk> wrote in message
news:1002881304.7119.0.nnrp-09.d4f07ab4_at_news.demon.co.uk...
> Hi
> I have a 8.0.5.2.2 server on HP-UX 10.20 running a massively busy OLTP
> instance.
> I have adjusted the checkpoint intervals to happen only during log
switches
> (every 20 minutes in Average load).
> Database has 69 datafile, 3 control files, and 4 DB_WRITER processes
> running.
> Every time a Log switch happens it exactly takes 3 minutes and users
suffer
> from hangings for some of this period. The redo log files are on two
> independent physical volumes separate from data files. The wait events
shoot
> up drastically during Log switch. I do not exactly know what could improve
> this situation. Would adding more DB Writers help, even though we have
only
> 2 CPUs on the server.
> I know this is not that straight forward and might need much more detail
> information to analyze the situation, however any indication toward right
> direction that I can take, or other factors that I have to look into,
would
> be a great help.
> Many thanks for any help, much appreciated.
> Regards
> Reza
>
>
>
>
>
Received on Fri Oct 12 2001 - 21:48:21 CDT
