The main wait events for block-related waits are:
gc current block 2-way
gc current block 3-way
gc cr block 2-way
gc cr block 3-way
The block-related wait event statistics indicate that a block was received as either the result of a 2-way or a 3-way message, that is, the block was sent from either the resource master requiring 1 message and 1 transfer, or was forwarded to a third node from which it was sent, requiring 2 messages and 1 block transfer.