If you've been following along, I've had quite a tough time with 16GB SGAs on 10.2.0.4. With help from Kevin Closson and Oracle Support, we found that the init.ora parameters "_db_block_cache_protect=true", "_db_block_check_for_debug=true", and "db_block_checking=true" cause 10.2.0.4 to not be able to allocate a 16G SGA. Not a problem in 10.2.0.3 mind you, but definitely a problem in 10.2.0.4.
In the end, it wasn't NUMA after all.
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