11.2.0.3 RAC Scenario

Dear Experts,

Could you please explain me on the below scenario

I have a two node 11.2.0.3 RAC database. lets assume one of the user is connected to the node 1 and performing the update operation on one of the table. In this scenario, The block which needs to update will be pulled into the memory by performing an I/O operation with the disk and will update the value ( Correct me if i am wrong) . Please stop by here

1) If second user connected from node 2 is trying to update the same block. I understood Global cache fusion will come into picture and will wait for the first user to commit ( I believe gc_cr_request and gc_buffer_busy are the wait events here).