Chapter 16. Latch and Mutex Contention
In the last chapter we examined Oracle locking mechanisms that exist primarily to prevent two sessions from simultaneously and inconsistently modifying the same data in a table. Latches and mutexes perform a similar function, except that instead of protecting data in tables, they protect data in shared memory.
You remember from Chapter 2, “Oracle Architecture and Concepts”—and elsewhere—that Oracle sessions share information in the buffer cache, shared pool, and in other sections of the shared memory known as the System Global Area (SGA). It’s essential that the integrity of SGA memory is maintained, so Oracle needs a way to prevent two sessions from trying to change the same piece of shared memory at the ...
Get Oracle now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
