Segment 11
This sub-session completed the implementation and GPU E2E validation of Phase 3 (cross-sector batching) for the cuzk pipelined SNARK proving engine. A BatchCollector was added to accumulate same-circuit-type proof requests, flushing when max_batch_size is reached or max_batch_wait_ms expires. A new multi-sector synthesis function (synthesize_porep_c2_multi) builds all N×10 partition circuits in a single combined pass, and split_batched_proofs separates the concatenated proof bytes back into per-sector results. GPU E2E testing on an RTX 5070 Ti with real 32 GiB PoRep data demonstrated a 1.46x throughput improvement for batch_size=2 over sequential single proofs, with peak RSS only ~2 GiB above baseline due to shared SRS. Non-batchable proof types preempt-flush any pending batch to avoid latency impact. The implementation is fully backward compatible (max_batch_size=1 preserves Phase 2 behavior), all 25 unit tests pass, and the commit is clean on the feat/cuzk branch.