Re: Row cache locks on INSERTs with a sequence

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Mon, 23 Dec 2002 08:49:16 -0800
Message-ID: <F001.00521463.20021223084916@fatcity.com>

Just as a side-line observation - when I realised that the problem should have been with the sequence, I set up a small test on a multi-CPU box to run multiple concurrent copies of:

    begin

        for i in 1..100000 loop
            insert into t1 values (test_seq.nextval);
        end loop;

    end;

I couldn't get a single row cache lock wait. This was using 8.1.7.4 on HPUX 11.

So I wonder if the waits you were seeing were a side-effect of another issue, or highly version dependent.

Regards

Jonathan Lewis
http://www.jlcomp.demon.co.uk

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-----Original Message-----
To: Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com> Date: 23 December 2002 14:40

>If I stated dc_segments in my original post, I apologize, I *did*
mean to
>say
>dc_sequences. At any rate, as usual, the problem was poor
application
>code.
>The row cache lock no longer shows up as one of the top 5 wait events
per
>statspack.
>
>And of course, the programmers never apologized, or even deigned to
>acknowledge
>appreciation in improving their application, they are simply acting
as
>offended
>cats will do, as though the DBA team doesn't exist.
>

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Author: Jonathan Lewis
  INET: jonathan_at_jlcomp.demon.co.uk

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Received on Mon Dec 23 2002 - 10:49:16 CST