Blog

Exadata Storage Configuration

The purpose of this post is to outline how storage works on Exadata.  We’ll look at the host-based storage on the compute nodes and storage server nodes, and then look at the cell storage characteristics, mapping these to ASM storage and finally, database storage. Environment Description The demonstrations in this document will be done using […]

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Oracle E-Business Suite, Exadata, and Smart Scan, Part II

In this post, I’m going do to a little follow-up to the blog at: https://centroid.com/oracle-e-business-suite-exadata-and-smart-scan/ I received quite a bit off both online and offline feedback on this post and wanted a chance to re-position my messaging a bit. First and foremost, the intent of my initial blog on the topic was *not* to recommend […]

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Direct Reads and Smart Scan with Exadata

Direct Reads and Smart Scan The most significant performance feature of Exadata is generally agreed to be smart scan.  There are several prerequisites for smart scan – most notably, the query must perform direct reads. The widely accepted (and published) stance on direct reads is that: – They take place for parallel operations (parallel direct […]

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Ditch Oracle Reports (RDF’s): Pure Play BI Publisher

I frequently encounter “pixel perfect” custom reports in both 11i and R12 that were created using Oracle Reports for data extraction into an XML stream then passed to the BI Publisher Output Post Processor for formatting, typically as a PDF. This leaves some great improvements in performance and flexibility in how we generate reports in […]

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Database Workload Replay in Oracle 11g

I recently attended RMOUG and saw a presentation for Database Workload Replay, a feature I’ve been meaning to take through its paces for quite awhile but never made time to test it out. Tonight I decided to give it a shot to see how difficult the process was, and as I discovered, it wasn’t too bad […]

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Managing Data in the 21st Century – Part 1

This is the first of a three part series on “How Smart Companies Manage Data in the 21st Century.” I am going to focus on trends and statistics for this first part and then as we progress, we will dive into how to get actionable information out of data. In the past 10 years, data […]

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DB Time, Average Active Sessions, and Some Scripts

Over the years, Oracle DBAs and developers have used different techniques to identify performance problems. Many books have been written, white papers published, blogs blogged upon, and so forth.  Nearly every Oracle DBA has the term “tuning” somewhere on their resume.  Common tuning approaches have included: Ratio based tuning (ugh) – Based on counters and […]

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Measuring Oracle 11gR2 RAC Waits

For quite some time, Oracle’s kernel has been well-instrumented to capture detailed wait event information.  Google “Oracle wait events” and you’ll come up with a wide range of great papers and publications about Oracle wait events, and also see http://docs.oracle.com/cd/E11882_01/server.112/e16638/toc.htm. Several cluster-specific wait events are populated in RAC environments. Wait class “Cluster” indicates cluster-related waits related […]

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Oracle Database Appliance Installation

Oracle Database Appliance Installation In this post I’m going to share  the end-to-end process of getting an Oracle Database Appliance (ODA) up and running at a client site.  No pictures, just words.   And right up front, I’m going to tell you this is likely going to be the shortest blog I’ll ever post on www.centroid.com/blog. […]

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Oracle Wait Events and Skew

First things First… Most savvy Oracle performance folks know about the 10046 extended trace file. If not, just Google “10046 trace” and you’ll learn all you need to know from a variety of sources.  Oracle’s tkprof utility provides a means to read the trace file and provide meaningful output, and recently (10g+) it’s had some […]

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Whatever we ask them to do, we know they'll deliver a solution and not leave us hanging.

Tony Deller Manager Data Center Technical Engineering