about the data dictionary cache

Can someone explain this statement?

"Large OLTP systems where users connect to the basis of their own user ID can explicitly benefit the owner of qualifying segment, rather than using public synonyms. This greatly reduces the number of entries in the dictionary cache. »

Thanks in advance

Claire wrote:
http://psoug.org/reference/synonyms.html

concerning

Yes, the statement is quite right but doesn't explain it well. I did a search and find Tom had discussion on it and claim the same. See the answer

On a small test, with one user, you can count the latch accesses and see significant differences
that may not appear to be terribly threatening . But with large numbers of users, the number of
'clones' of objects with the same name in the same namespace and therefore on the same latch, goes
up, and the time taken to search a chain can become a serious threat if everyone is trying to
access some information about their verion of the 'same' object.  The scale of the problem is order
n-squared with respect to the number of different users.

Tom reviews the issue of scalability using the public synonym. As the number of users increases it would have more cloned copies Similarly, and they would be protected under lock and key, if of locking issues. I'll nedopil my previous post so that others don't get confused. And it was a kind of larning for me as well. Thanks for asking this question.

Link - http://asktom.oracle.com/pls/asktom/f?p=100:11:0:P11_QUESTION_ID:7555433442177 #7640980652786

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