About

Martin Klier

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Oracle RAC 12.2 on SLES12 – How to disable Hardware Lock Elision Support

The Problem In the last week, I had to set up an Oracle RAC (and thus, the Clusterware) version 12.2.0.1 on SuSE Linux Enterprise Server 12 SP2 (SLES12 Sp2). The gridSetup.sh failed latest in root.sh of the first node with a kinda non-intuitive error: CRS-5804: Communication error with agent process CRS-4000: Command Start failed, or […]

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Restarting Oracle for Performance is like a Coitus for Virginity

Today I had another case of that … total breakdown of a live environment by infrastructure defect, bad enough. Customer rushing up the database and all apps services, just to see thousands of locks and hanging transactions. Big panic, frequent restarting of databases and applications. Getting worse, finally calling me. Told them I’ll manage that, asked […]

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Oracle RMAN destination with variable restrains “not backed up” clause

Today I was a bit surprised – being always under the impression that Oracle RMAN should accept “backup backupset not backed up to destination ‘xyz’” AND work with it successfully. But I learned that in 11.2.0.4 the Oracle RMAN “to destination” containing variables restrains the “not backed up” clause. No error thrown, but just does not work […]

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Oracle Database 12.2 on-premises release dates

Oracle recently announced the availability of Oracle Database 12c release 2 (12.2) for on-premises servers. https://www.performing-databases.com/en/2017/01/oracle-database-12-2-on-premises-release-dates/ Linux x86-64, Solaris SPARC and Solaris x86-64: 15-Mar-2017 Other supported platforms (Windows x86-64, IBM AIX on POWER, IBM Linux on System z, HP UX Itanium): Q2CY2017 Source: MOS DOc ID 742060.1 […]

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Oracle Automatic Big Table Caching – an improvement, not a fix

Too much TABLE ACCESS FULL in your Oracle Database? Thus, SQL elapsed time too slow for the demand? Plenty of Buffer Cache to create a temporary fix? maybe you want to consider Automatic Big Table Caching. Usually, Oracle only does Full Table Caching for small tables. Big ones will only use the Buffer Cache for the current chunk […]

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Oracle 11g unable to extend datafile but ASM disk group shows free space

Sometimes Oracle Database 11gR2 complains about not being able to extend a (lob) segment with ORA-1691, but ASM monitoring based on USABLE_FILE_MB did not fire. Adding a new data file fails with ASM ORA-15041. I was under the impression this behaviour of ASM deserved some explanation. Situation Database Alert Log complains with ORA-1691: ORA-1691: unable to extend lobsegment MYUSER.SYS_LOB0013128030C00003$$ […]

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My COLLABORATE16 look-at’s – an aftermath

From April 10th to April 14th 2016 many Oracle professionals congregated in Las Vegas. The three big U.S. user groups, the IOUG, the OAUG and the Quest User Group once again formed one of the best Oracle Conferences in the world: COLLABORATE16. I was honored to be there as a speaker, and glad to perform […]

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