Performance

DBA, Partitioning, Performance

Improving data move on EXADATA III

TweetShareSharePin0 SharesMoving to history tables In the last post I talked about how we made the speed of actually writing all those log-records much faster. It has to date been so fast that no a single report of a problem has been filed. you find that post here. Once the data was written to the log-tables, it had to be moved to the history tables.This was a process that took around 16 hours. It was never allowed to run for […]

DBA, Partitioning, Performance

Improving data move on EXADATA II

TweetShareSharePin0 SharesWriting log records The last post in this series introduced the problem briefly. You find that post here. In this post I’ll talk about the changes made to make that writing of log records fast enough. There were 50 million records that was written. Each of them pretty much in its own transaction. Of course the commit activity caused problem, as did log buffer issues. Some of this could be somewhat remedied with configuration. The big issue though was that […]

Partitioning, Performance, DBA

Faster data move on EXADATA I

TweetShareSharePin0 SharesIntroduction In my work among other things I tune and tweak solutions for EXADATA. Today I’ll write about a big improvement we achieved with a process that moves data from the operational tables to the ones where the history is stored. This will not be a technical post. While I talk about using advanced technologies, I will not discuss code or deep details of them in this post. And yes, when I say post, I mean a series of […]

DBA, OOW, Oracle, Performance, SQL, APEX

OOW 2010 Develop Keynote

TweetShareSharePin0 SharesYes, this post is a little out of order as it clearly didn’t take place after the Thursday afternoon sessions. I missed it during the conference so I had to catch up on it later on the on demand site. I thought it was interesting enough to write up a few notes. It was held by Tom Kyte and the subject was “What’s new in database development”. It’d be more correct to say Oracle development than database development as […]

OOW, Oracle, Performance

OOW 2010 Thursday Afternoon

TweetShareSharePin0 SharesFor the afternoon I had two sessions I attended. The first was “Quantifying Oracle Performance” and the second was “The X-files – Managing exadata and highly available databases”. I anticipated both to be great and possible be among my favorites for the week. Unfortunately neither met my expectation, so this is going to be a fairly short post. The first one was “Quantifying Oracle Performance” with Craig Shallahamer, I have seen many presentations with Craig and he has always been […]

OOW, APEX, Oracle, Performance, SQL

OOW 2010 Thursday Morning

TweetShareSharePin0 SharesThe day starts with a presentation b6 Tom Kyte about “What else can you do with system and session data”. Tom starts with reviewing the history of tuning an Oracle database. The prehistoric era (v5) required writeing debug code as that was the only way to get any information about what the code did. The dark ages followed (v6) and now Oracle introduces: Counters/ratios bstat/estat SQL Trace The first few (7?) v$-views are introduced In the renaissance era (v7) […]

APEX, OOW, Performance

OOW 2010 Starts

TweetShareSharePin0 SharesI arrived to San Francisco yesterday and OOW kicked off today. The efficiency at the registration alone was impressive. The lines we’re very long, but it probably took less than 15 minutes to get through it. This post will essentially be a dump of notes from the sessions I attended. The first session was the start of the APEX symposium. It was supposed to feature Scott Spendolini and an overview of APEX 4.0. He had been delayed so the […]

ITL, Oracle, Performance

Interested Transaction List

TweetShareSharePin0 SharesInterested Transaction List is the method through which Oracle keeps track of which transaction has updated which row in a block. I wrote an article about it a while back where I show how the ITL works and how it impacts performance in certain situations. The basis of the article is a page locking scenario I encountered. Sure, page locking is not possible in Oracle, but an ITL wait is very similar to a page lock.  You find the […]