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Home -> Community -> Mailing Lists -> Oracle-L -> Re: Suggestions Needed: Latch free - library cache
> > To the OP: Other people point out common reasons for library cache latch
> > contention. A less common reason is extensive use of public synonyms.
> > If that's the reason, you also see row cache objects latch contention.
>
> I'm not sure that's right. If everyone uses a public synonym, then
> you get one sql text, and one cursor. I think the contention appears
> because everyone has to have a 'non-existent' reference in memory
> to say that they don't own an object with the same name as the public
> synonym - consequently if you have lots of users who have to check
> long chains of 'non-existent' then the latches get held for longer
> periods of time.
Hi Jonathan,
I don't see how your statement contradicts the claim that heavy use of public synonyms causes contention for not only library cache latches but also row cache objects latches. What I had in mind is Steve Adams' test. Here's the URL http://www.ixora.com.au/newsletter/2001_05.htm#synonyms. If I understand right, the additional row cache objects latch gets are for synonym translations, particularly public synonym translations.
Yong Huang
-- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Yong Huang INET: yong321_at_yahoo.com Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).Received on Fri Jan 09 2004 - 11:09:31 CST
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