A Sub-Prime I/O Primer

My fans on oracle-l already know that I've had a bit of a battle with Oracle I/O recently, most of the damage being self-inflicted. I'd like to give as forensic a review as possible so that those poor souls who come after me will have some hope and inspiration to... [Read More]

DBWR and the Devil

I was recently re-reading parts I, II, III and IV of Kevin Closson's series on the perils of overconfiguring your db_writer_processes (which I mentioned earlier this year). My instance appeared to be a perfect candidate. It was configured with db_writer_processes=4, using the one-DBWR-for-each-CPU approach that Kevin rails against for most... [Read More]

Greg Rahn Explains Plans

Greg over at Structured Data has a fantastic piece titled "Troubleshooting Bad Execution Plans" which is a must-read for all. Learning about the GATHER_PLAN_STATISTICS hint alone was worth the price of admission.Also time for me to re-evaluate the changes I made to OPTIMIZER_INDEX_CACHING and OPTIMIZER_INDEX_COST_ADJ a few versions back:SQL> show... [Read More]

Scalar::Util on CentOS5 is Bustinated

While trying to install pastebot on my CentOS5 sandbox for interal IRC usage, I found that I had to install a number of other perl modules upon which pastebot depended. This however became very frustrating as nearly all of them failed.I ended up following the dependency chain to eventually find out that IO::Compress::Base... [Read More]

Tuning Backup & Recovery

A level 0 database backup of my production instance takes over 8 hours, and duplication is just as long, if not longer. I’m going to do some reading and see if we can shore things up. I’ll report back.  The database is around 1.1 terabytes.  Some have told me that their databases... [Read More]