Posts

Global Cache Service Processes in a Oracle Cluster (RAC) with Multiple Databases

Creating a cluster with a single pool of storage managed by Oracle ASM provides the infrastructure to manage multiple databases whether they are single instance databases or Oracle RAC databases. With Oracle RAC databases, you can adjust the number of instances and which nodes run instances for a given database, based on workload requirements. Features such as cluster-managed services allow you to manage multiple workloads on a single database or across multiple databases. It is important to properly manage the capacity in the cluster when adding work. The processes that manage the cluster—including processes both from Oracle Clusterware and database—must be able to obtain CPU resources in a timely fashion and must be given higher priority in the system.

RMAN Configuration in Data Guard [Archivelog Deletion Policy]

Follow these steps to configure RMAN backups in Data Guard environment. When you want to managed the archivelog deletion policy from one centralpoint. CONFIGURE ARCHIVELOG DELETION POLICY Possible options : APPLIED ON STANDBY - enables flash recovery area to delete archivelogs that are applied on mandatory standby. NONE - enables flash recovery area to delete archivelogs that are backed up to tertiary device and that are obsolete based on the configured backup retention policy. This is the default configuration. CLEAR - clears the deletion policy and returns the specified configuration to default value. The default value is NONE.

ASM required mirror free space to accommodate disk failures

Blogpost Dutch Prutser January 2 2013 03/01/2013 The summary of the blogpost REQUIRED_MIRROR_FREE _MB is the amount of free space required to restore redundancy after a failure that ASM can tolerate without affecting data availability. This amount depends on the redundancy level and the number of failure groups in the disk group.  Normal redundancy disk groups with at least three failure groups require an amount of free space that is equal to the size of a single failure group. Normal redundancy disk groups with only two failure groups require an amount of free space that is equal to the size of a single disk.  High redundancy disk groups with at least four failure groups require an amount of free space that is equal to the sum of the size of two failure groups. High redundancy disk groups with only three failure groups require an amount of free space that is equal to the sum of the size of two disks.  USABLE_FILE_MB is the amount of disk space available for stor...

Use Chrome plugin to make Oracle AWR reports (formattter) friendly

Blogpost of Tom Kyte Thursday, April 28, 2011 An " AWR Formatter " written by a friend of mine, Tyler Muth. It's pretty cool - works as a Chrome plugin - and it makes an AWR report a little more 'friendly' to use. It creates hot links for many of the wait events (so you know what they mean) and it summarizes up a lot of stuff - making the AWR report a lot more "interactive". Check it out and give him feedback on it if you have time.  

Use Firefox Quick Searches to quickly access Oracle related information: DOCs, SRs, NOTEs, BUGs etc…”

Customize your Firefox to use acronym and contents of mentioned Metalink Note displayed without the need to open Metalink web site. “mn 1269139.1″ ( mn was an acronym for Metalink Note)  How to do this see the blog of   Oleksandr Denysenko's Blog

Patch for Enterprise Manager Database Control 10.2.0.4 Or 10.2.0.5

The Problem Enterprise Manager Database Control with Oracle Database 10.2.0.4 and 10.2.0.5 " The DBCONSOLE" will not work. The root certificate used to secure communications via the Secure Socket Layer (SSL) protocol will expire on 31-Dec-2010 00:00:00.  ATTENTION - Enterprise Manager Database Control 10.2.0.4 Or 10.2.0.5 - Patch Required from 31-Dec-2010 onwards [ID 1217493.1] Solving this problem If you plan to configure Database Control with either of these Oracle Database releases, Oracle strongly recommends that you apply   Patch 8350262   to your Oracle Home installations before you configure Database Control. Configuration of Database Control is typically done when you create or upgrade Oracle Database, or if you run Enterprise Manager Configuration Assistant (EMCA) in standalone mode.

Bug 9981011: VARIOUS ORACLE PROCESSES CONSUMING LARGE QUANTITIES OF FILE DESCIPTORS (NFILES)

After upgrading to the 10.2.0.5.0 release the database is encounter a file handle leak.  The leak is seen in production and development instances. The leak happens on different processes (emagent and MMNL process are the current ones).  Test on growing of openfiles: lsof -p 10140 |wc -l => 600 lsof -p 10140 |wc -l => 759 Now we wait for the sollution of oracle to solve this bug. The max file limit has been reached so the db will have to be shutdown or the  process killed, if possible, to free up files. The leak happen over time and manifests itself when the limits are reached as error ORA-27041. The sollotion VARIOUS ORACLE PROCESSES CONSUMING LARGE QUANTITIES OF FILE DESCIPTORS (NFILES) Patch 9981011 . For us we need the  Patch download for Oracle 10.2.0.5 on HP-UX Itanium. This patch is also suitable for a 10.2.0.5.1 home, there are no conflicts with 10.2.0.5.1