Re: Fun with WAIT Event "library cache: mutex X"
From: Grzegorz Goryszewski <grzegorzof_at_interia.pl>
Date: Thu, 08 Dec 2011 19:49:03 +0100
Message-ID: <4EE1069F.8000101_at_interia.pl>
On 2011-12-08 19:24, Gaja Krishna Vaidyanatha wrote:
> But, I am still old school when it comes to buffer cache sizing, shared pool & other pools sizing. I believe it should be part of a DBA's job and should be automated ONLY in applications/databases that demonstrate consistent, predictable and static behavior in workloads. For more dynamic and inconsistent workloads, I personally would go with manual memory settings. It is worthwhile incurring the additional cost of allocating more memory for the required structures and gain stability and consistency in return. Plus, the CPU overhead of MMAN (if and where relevant) can be avoided.
>
>
Please consider, despite of disabling AMM Oracle still fights back via: *"SGA Re-Sizes <javascript:;> Occurring Despite AMM/ASMM Being Disabled (MEMORY_TARGET <javascript:;>/SGA_TARGET <javascript:;>=0) [ID 1269139.1]"
Date: Thu, 08 Dec 2011 19:49:03 +0100
Message-ID: <4EE1069F.8000101_at_interia.pl>
On 2011-12-08 19:24, Gaja Krishna Vaidyanatha wrote:
> But, I am still old school when it comes to buffer cache sizing, shared pool & other pools sizing. I believe it should be part of a DBA's job and should be automated ONLY in applications/databases that demonstrate consistent, predictable and static behavior in workloads. For more dynamic and inconsistent workloads, I personally would go with manual memory settings. It is worthwhile incurring the additional cost of allocating more memory for the required structures and gain stability and consistency in return. Plus, the CPU overhead of MMAN (if and where relevant) can be avoided.
>
>
Please consider, despite of disabling AMM Oracle still fights back via: *"SGA Re-Sizes <javascript:;> Occurring Despite AMM/ASMM Being Disabled (MEMORY_TARGET <javascript:;>/SGA_TARGET <javascript:;>=0) [ID 1269139.1]"
Regards
GregG
*
-- http://www.freelists.org/webpage/oracle-lReceived on Thu Dec 08 2011 - 12:49:03 CST