A DML behaves on RAC in a similar manner as on a single node instance except a small change.
Each node on RAC has its own buffer cache. In CASE of DML, it looks for the data block in a local cache. If the current COPY of block is not PRESENT, cache FUSION is applied to get the latest copy from the local cache of other blocks. If this is not possible then the block is read into the local cache from disk and updated similar to a single node instance. The buffer cache of other blocks is fused with the current block later as required.

A DML behaves on RAC in a similar manner as on a single node instance except a small change.
Each node on RAC has its own buffer cache. In case of DML, it looks for the data block in a local cache. If the current copy of block is not present, cache fusion is applied to get the latest copy from the local cache of other blocks. If this is not possible then the block is read into the local cache from disk and updated similar to a single node instance. The buffer cache of other blocks is fused with the current block later as required.