Re: Rollback Contention

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Sun, 20 Feb 2000 19:27:54 -0000
Message-ID: <951075030.25957.1.nnrp-02.9e984b29@news.demon.co.uk>

It seems a little unlikely give the number of uses, and number and size of segment. Did the consultant say what the evidence was that suggested rollback contention ?

Unless the algorithm has changed recently Oracle does a round-robin in the order that the segments were listed in the init.ora or brought online, restricting itself to rollback segments that currently have the least
number of active transactions.

Jonathan Lewis
Yet another Oracle-related web site: http://www.jlcomp.demon.co.uk

DianeB wrote in message <88pc69$inq$1_at_newsg2.svr.pol.co.uk>...
>I have just been told my a consultant that on looking at the database I may
>well have a rollback contention problem.
>
>Can anyone please tell me a quick and easy way of establishing if he is
>right. My rollback segments are configured as follows:-
>
>No of Rollback segments 35
>
>Initial Extent 1M Next 1M
>
>Optimal Size 10M
>
>The database is for Oracle Financials 10.7 with roughly 150 users.
>
>Also could someone give me in real simple terms what the rules are for
>deciding which rollback segment is chosen by
>a new transaction.
>
>Many Thanks
>DB
>
>
Received on Sun Feb 20 2000 - 13:27:54 CST