Troubleshooting Another Complex Performance Issue – Oracle direct path inserts and SEG$ contention

Here’s an updated presentation I first delivered at Hotsos Symposium 2015.

It’s about lots of concurrent PX direct path insert ant CTAS statements that, when clashing with another bug/problem, caused various gc buffer busy waits and enq: TX – allocate ITL entry contention. This got amplified thanks to running this concurrent workload on 4 RAC nodes:

When reviewing these slides, I see there’s quite a lot that needs to be said in addition to what’s on slides, so this might just mean a (Powerpoint) hacking session some day!

NB! After a 1.5 year break, this year’s only Advanced Oracle Troubleshooting training class (updated with Oracle 12c content) takes place on 16-20 November & 14-18 December 2015, so sign up now if you plan to attend this year!