poor clob performance with very high CPU

From: Josh Collier <Josh.Collier_at_banfield.net>
Date: Mon, 2 Nov 2009 11:30:25 -0800
Message-ID: <C5671700C5F4EA47B08AB9E6DAE9539B37EB6258B0_at_M1EXCHANGE01.mmi.local>

Solaris 10 update 4 on SPARC


I have a CTAS that involves a CLOB. The expected duration of this process is 180 minutes. Recently it started taking > 5 hours. The data and rowcounts are very similar, the trace shows only CPU consumption and very little else. I am wondering if you guys have any insight into how to diagnose a clob performance issue where the only information I have is excessive CPU consumption.

The execution paths have not changed. These are staging tables and they never have statistics as we always want full tablescans. The tablespaces underlying the tables/clobs have not changed. They are local ASSM with uniform extent sizes of 128k.

Thanks for your time,

Josh C.

Received on Mon Nov 02 2009 - 13:30:25 CST

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