Ardent Performance Computing
Linux
Did Postgres Lose My Data?
Hello, let me introduce myself. Today, we’ll pretend that I’m a linguistics researcher. I don’t know much about databases, but I do know a lot about the Balti language of northern Pakistan. That’s why I’m excited about my current translation project. The most interesting part of this translation project is that I’m doing some computer-driven … Continue reading
Researching the Performance Puzzle
The PostgreSQL Performance Puzzle was, perhaps, too easy – it didn’t take long for someone to guess the correct answer! But I didn’t see much discussion about why the difference or what was happening. My emphasis on the magnitude of the difference was a tip-off that there’s much more than meets the eye with this … Continue reading
PostgreSQL Invalid Page and Checksum Verification Failed
At the Seattle PostgreSQL User Group meetup this past Tuesday, we got onto the topic of invalid pages in PostgreSQL. It was a fun discussion and it made me realize that it’d be worth writing down a bunch of the stuff we talked about – it might be interesting to a few more people too! … Continue reading
Understanding CPU on AIX Power SMT Systems
This month I worked with a chicagoland company to improve performance for eBusiness Suite on AIX. I’ve worked with databases running on AIX a number of times over the years now. Nevertheless, I got thrown for a loop this week. TLDR: In the end, it came down to a fundamental change in resource accounting that … Continue reading
Lessons from Africa, Part 2
Last week was busy… making travel arrangements for this week’s trip to New York (technically Jersey) and some light analysis of AWR reports from exadata RAT runs and some heavy troubleshooting of a Solaris x86 RAC cluster with random node reboots. (I think I finally traced the node reboots to a kernel CPU/scheduling problem). I … Continue reading
Lessons From Rural Africa
It has been nine months since I’ve written here. Needless to say, a lot has happened! First, my family was living in Africa for three months earlier this year while I did some tech work at an NGO hospital. Second, upon our return I decided to join the good people at Pythian. I’m not moving … Continue reading
RAC Attack – Oracle Cluster Database at Home
First of all, the RAC Attack deep dive at Collaborate went great – thanks to everyone who participated! The room was full (20 participants) and I got evaluations from about half of them. Here’s a summary of the eval results: 100% class met expectations, would recommend to others 66% easy to follow, could use skills … Continue reading
Mysterious Oracle Net Errors
Yesterday, I had a fight to the death with a nasty Oracle Net problem. The battle consumed a little more of the day than I intended… but it was worthwhile for the sweet taste of victory. Everything started with this short, innocent-seeming instant message: there is something wrong with a 10g server config. connecting to … Continue reading
RAC Investigation on Low-Memory Linux
Back in the Oracle 9i days, I was one of those people who got on eBay to buy firewire PCI cards and disks that could do non-exclusive login. Remember that? The first time a little test cluster could be cheap enough for the home enthusiast? I still have the parts in my closet. Of course, … Continue reading
Future of OCFS2
At the company where I’m working right now, I’m part of an architecture effort to come up with our standard design for RAC on Linux across the firm. There will be dozens or possibly hundreds of deployments globally using the design we settle on. We’re internally debating whether or not we should include OCFS2 in … Continue reading
Disclaimer
This is my personal website. The views expressed here are mine alone and may not reflect the views of my employer.
contact: schneider @ ardentperf.com
Ardent Performance Computing 
Recent Comments