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Re: RAC problem, is gc_files_to_locks is needed?

From: biti_rainy <biti_rainy_at_itpub.net>
Date: Thu, 21 Oct 2004 13:18:17 +0800
Message-Id: <20041021051840.4BC8072C6BD@turing.freelists.org>


hi,tomi wijanto

  from oracle document

Setting this parameter to any value other than the default will disable Cache Fusion processing in Oracle9i Real Application Clusters.

from
Oracle Real Application Clusters
by Murali Vallath

Local
 When the block is read for the first time into an and there are no other instances in the cluster that have read the same block or are holding the block, then the block is locally managed  

Global
 If the block that was originally acquired has been modified by the holding instance and, based on a request from another instance, has transmitted the block over. The block that was originally on one node is now present in multiple nodes and therefore is considered globally managed  

When an instance reads data blocks for the very first time, its existence is local, that is, no other instance in the cluster has a copy of the same block. The block in this state is called a current state block (XI). Therefore, the behavior of this block in memory is similar to any single instance configuration, with the exception that GCS keeps track of the block even in a local mode. Multiple transactions within the instance have access to these data blocks. Once another instance has requested for the same block, then the GCS process will update the GRD, taking the state of the data block from a local role to a global role.

Best regards

msn: biti_rainy_at_hotmail.com
a dba from alibaba(china)

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Received on Thu Oct 21 2004 - 00:14:15 CDT

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