To discover how the Oracle latch works, we need the tool. Oracle Wait Interface allows us to explore the waits only. Oracle X$/V$ tables instrument the latch acquisition and give us performance counters. To see how latch works through time and to observe short duration events, we need something like stroboscope in physics. Likely such tool exists in Oracle Solaris. The DTrace, Solaris 10 Dynamic Tracing framework!
Here I would like to give brief, Oracle DBA inclined into to some of DTrace topics. Tanel Poder, James Morle , Dough Burns were used the DTrace for performance diagnostics for years. But it is still not popular as should be in our DBA community. One of the problems is another “language”. The best DTrace presentations talk about “probes”, “actions”, unfamiliar Solaris kernel structures, etc… Begging pardon to the DTrace inventors, I will use more database-like terminology here.
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Latch, mutex and beyond 