Latch, mutex and beyond

March 19, 2011 is the right patchset for mutexes

Filed under: 11.2,Mutex,Patches — andreynikolaev @ 10:05 am

Many people asked me about the second part of my blog title – the mutex. This is the first post about it. Mutexes is another Oracle spinlock, which was appeared in version Despite being known since 2005, Oracle mutex internals is still Terra incognita.

This post is inspired by several recent escalations due to mutex contention. It occurs that patchset contains extraordinary number of mutex related changes. Some enhancements like 10411618 exist only for The following patches even changed the mutex architecture: (more…)

March 15, 2011

Hotsos 2011 Symposium follow-up

Filed under: Uncategorized — andreynikolaev @ 9:58 pm

Just returned from the Hotsos 2011 Symposium. It was an exciting experience to be speaker at this legendary conference. Many thanks to the Hotsos team for this opportunity.
The Symposium and the presentations were inspiring. I hope my presentation was interesting too. It had to be concise because of one hour time limit. Usually these topics discussed during almost half of my training day. I will cover the topics more detaily in future posts.

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