Re: Why not set all sessions to resumable?

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Sat, 6 Mar 2004 07:04:50 -0000
Message-ID: <034e01c40349$536943c0$7002a8c0@Primary>

This is on my todo list to check, but when a session has resumable roles enabled, it seems to updates a dynamic performance table (under v$resumable_operations or some such) for every operation made.
Since the dynamic performance view has to be accurate and in the SGA, it may be that there is a single latch protecting a single linked list of data.

If this surmise is true, then some systems could suffer a lot of contention for this latch - imagine a session performing 1M single row inserts.

One day I'll have time to look into it.

Regards

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

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Original Message ----- From: "Jesse, Rich" <Rich.Jesse_at_quadtechworld.com> To: "ORACLE-L (E-mail)" <oracle-l_at_freelists.org> Sent: Saturday, March 06, 2004 12:38 AM Subject: Why not set all sessions to resumable?

: Hey all,
:
: As I'm reading about the new (relatively speaking) features of 9i, I see
the
: "ALTER SESSION ENABLE RESUMABLE" statement. What's the catch? I haven't
: been able to find out why you wouldn't set this on a process, or in some
: cases, all user processes in an instance.
:
:

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Received on Sat Mar 06 2004 - 01:02:05 CST