Re: What would happen if..?

On Mar 15, 6:15 pm, Yong Huang <yong..._at_yahoo.com> wrote:
> On Mar 14, 10:23 am, Ben <benal..._at_yahoo.com> wrote:
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> > 10.2.0.2 EE, aix 5.2 64bit
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> > I have seen the metric reported in Enterprise Manager several times
> > for "Current Open Cursors Count" on one of our database's home page/
> > screen. It's reporting it at 7828. This particular system has about
> > 1200 individual sessions logged on during peak hours and drops down to
> > about 500 during off hours. OPEN_CURSORS is set to 500 in this
> > database.
>
> > What I don't understand is exactly why this metric is being reported
> > to me and if it is just a default value that it has decided once there
> > are x number of open cursors the threshold has been crossed and I'm
> > going to raise a warning.
>
> > I guess what I'm really asking is, is there some magic number of open
> > cursors that I should be worried about, or is it just reporting this
> > open cursor count because by default there is a threshold set at 1200
> > open cursors that it is at warning status.
>
> > Is there some maximum number of open cursors for the entire instance
> > that if we reach that number it's going to blow up shoot sparks out of
> > the back of the server....
>
> Ben,
>
> You may already know this. But just in case. EM's alert at 1200 opened
> cursors is system wide, not for a single session. So it doesn't make
> much sense. Instead of looking at v$sysstat for 'opened cursors
> current' as EM does, you can write your own monitoring script based on
> v$sesstat for statistic# 3 (10g). If it either approaches a preset
> limit such as 90% of open_cursors or (more challenging) monotonically
> goes up for a preset period of time, send an alert.
>
> Yong Huang- Hide quoted text -
>
> - Show quoted text -

Thank you for the info, I did know that was an overall system count. That's really why it didn't make much sense to me. Seems like a useless metric to me. I looked back at the history of open cursors and we consistently have around 14,000 during peak hours and drop down to about 2000 during off hours, so I reset the threshold to 16,000 to warn me. Received on Mon Mar 17 2008 - 07:14:53 CDT