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Hi Herman
Have you verified that 16 slaves are running? Check your parallel_max_servers and parallel_automatic_tuning parameters. Make sure the former is sufficiently high.
Hth,
Ivan Bajon
"Herman de Boer" <h.de.boer_at_itcg.nl> wrote in message
news:bde5777e.0111010713.10d774b8_at_posting.google.com...
> Dear *,
>
> I am investigating a site running RDBMS 8.1.6.2.0, on HP V2500, UX11,
> 2Gb memory, a 4-cpu box hosting a ~400 Gb database with Parallel
> Query.
>
> Most time is spent in event PX qref latch, with parallel degree 8 (so
> 16 slaves are running), with about 50% idle time (as given by top).
> There is a certain amount of disk I/O, but far below the bandwidth.
> Complex sql-statements, mostly pctas.
>
> Anyone useful hints or advice or information what this event is about,
> and why so much time is spent in this one?
>
> Kind Regards,
>
> Herman de Boer
> IT Consultancy Group bv
Received on Fri Nov 02 2001 - 08:44:43 CST