Gavin Hamill <gdh@xxxxxxxxxxxxx> writes: > This is one hell of a moving target and I can't help but think I'm just > missing something that's right in front of my nose, too close to see. I'm assuming you compiled postgres yourself? Do you have the output from the configure script? I'm wondering if it failed to find a good spinlock match for the architecture. Not sure if that's really likely but it's a possibility. Also, I'm pretty sure IBM has tools that would let you disable some of the processors to see if maybe it's a shared memory bus issue. If I understand you right the machine isn't in production yet? In which case I would get timing information for a single processor, two processors, four processors, and eight processors. If you see it max out and start dropping then that would point towards a hardware/low level postgres issue like spinlocks or shared memory rather than a high level database issue like stats. -- greg