Re: Corporate Wide Public Synonyms

Richard Foote wrote:
> <yong321_at_yahoo.com> wrote in message
> news:1108131913.154821.319710_at_g14g2000cwa.googlegroups.com...
> > Richard Foote wrote:
> >> <linuxgeek_00_at_yahoo.com> wrote in message
> >> news:1108068838.968042.219230_at_f14g2000cwb.googlegroups.com...
> >>
> >> At a site I work, they previously had a couple of thousand or so
> > users
> >> accessing everything through public synonyms. Latch contention was
a
> >> significant performance bottleneck.
> >>
> >> By using setting the appropriate current_schema via a logon
trigger,
> > the
> >> associated latch contention issues pretty well vanished.
> >
> > Hi, Richard,
> >
> > Do you remember what latch the contention was on? It must be
library
> > cache latch I guess. Any other one? Thanks.
> >
>
> Hi Yong
>
> In varying degrees, the latch contention was on library cache latch,
the
> shared pool latch and the row cache objects latch. One other point I
didn't
> mention was the CPU consumption was also reduced to a significant
degree.
>
> Cheers
>
> Richard

Thanks, Richard. You probably guessed why I asked. The one I wanted to see is row cache objects latch. (Ref.
http://www.ixora.com.au/q+a/0101/05095229.htm and other notes on the site.) Contention on this latch is not a big performance problem in itself, not as much as on library cache and shared pool latches. But it serves as a good indicator of using public synonyms too much.

Yong Huang Received on Mon Feb 14 2005 - 14:06:33 CST