Chunk 11.1
This chunk documents the implementation and GPU E2E validation of Phase 3 (cross-sector batching) for the **cuzk** pipelined SNARK proving engine. The core architectural addition is a `BatchCollector` that accumulates same-circuit-type (PoRep, SnapDeals) proof requests, flushing them when `max_batch_size` is reached or `max_batch_wait_ms` expires. A new `synthesize_porep_c2_multi()` function in the pipeline layer takes N sectors' C1 outputs, builds all N×10 partition circuits, and performs a single combined synthesis pass. After GPU proving, `split_batched_proofs()` separates the concatenated proof bytes back into per-sector results, and each caller receives its individual proof with accurate timings. Non-batchable proof types (WinningPoSt, WindowPoSt) preempt-flush any pending batch and process immediately, ensuring no latency impact on priority-critical proofs. GPU E2E testing on an RTX 5070 Ti with real 32 GiB PoRep data validated the implementation with detailed memory monitoring. The baseline (batch_size=1, single proof) completed in 88.9s total (synthesis 59.3s, GPU 28.8s) with ~5.5 GiB RSS memory. With batch_size=2 and two concurrent proofs, the daemon accumulated both requests and processed them as a single batched pass: total time 121.6s for both proofs (60.8s per proof steady-state), with peak RSS ~7.5 GiB (only ~2 GiB above baseline). This represents a **1.46x throughput improvement** over sequential single proofs (2 proofs in 121.6s vs 177.8s), with memory overhead far lower than the theoretical 2x because the SRS (47 GiB pinned) is shared and only the compressed auxiliary assignments grow linearly with batch size. The implementation is fully backward compatible — `max_batch_size=1` preserves Phase 2 behavior exactly. All 25 unit tests pass with zero warnings, and the commit is clean on the `feat/cuzk` branch (9 commits total). The roadmap now advances to Phase 4 (compute optimizations: SmallVec, parallel B_G2 MSMs, pinned memory transfers) and Phase 5 (Pre-Compiled Constraint Evaluator), with cross-sector batching already delivering measurable throughput gains on production hardware.
From Architecture to Throughput: The Complete Story of Phase 3 Cross-Sector Batching
Message Articles
- The Architecture of a Single Instruction: How "Implement Phase 3" Transformed Filecoin Proving Infrastructure
- The Deliberate Engineer: Why the First Step Toward Phase 3 Was to Read, Not Write
- The Pivot Point: How Reading Three Files Unlocks Cross-Sector Batching
- Reading the Blueprint: How a Single Information-Gathering Message Enabled Cross-Sector Batching in a SNARK Proving Engine
- The Methodical Reader: How a Single Message Reveals the Engineering Behind Cross-Sector Batching
- The Architecture of a Plan: Designing Cross-Sector Batching for the cuzk SNARK Proving Engine
- The Pivot Before Implementation: How One Message Completed the Picture for Phase 3 Cross-Sector Batching
- The Architecture of Cross-Sector Batching: A Design Pivot in the cuzk Proving Engine
- The First Stone: Writing the Batch Collector for Phase 3 Cross-Sector Batching
- The Pivot Point: Adding `synthesize_porep_c2_multi()` and the Architecture of Cross-Sector Batching
- The Unsung Hero of Batched Proofs: Why a Single Test Defines Phase 3 Correctness
- The Module Declaration That Made Phase 3 Real
- The Status Update That Moves Mountains: A Todo Tracker's Role in Engineering a SNARK Proving Engine
- The Integration Point: Rewiring the Engine for Cross-Sector Batching
- The Integration Point: Wiring Cross-Sector Batching into the cuzk Proving Engine
- The Pivotal Bridge: Adding `process_batch` to Complete Phase 3 Cross-Sector Batching
- The Final Link: Updating the GPU Worker for Cross-Sector Batch Proving
- The Missing Default: A Small Trait Implementation That Unlocks a Pipeline
- The Status Update That Speaks Volumes: A Todo List as an Architectural Milestone
- The Final Piece: Documenting Batch Configuration in the cuzk Proving Engine
- The Build That Confirms: A Verification Milestone in the cuzk Phase 3 Pipeline
- The Clean Build: A Pivotal Moment of Validation in the cuzk Proving Engine
- The Moment Between Milestones: Why "All 25 Tests Pass" Matters More Than You Think
- The Quiet Discipline of Zero Warnings
- The Final Verification: How a Single Test Run Confirms Phase 3 of the cuzk Proving Engine
- The Final Gate: Why a Warning Check Marks the True Completion of a Feature
- The Quiet Milestone: How a Single Status Message Marked the Completion of Phase 3 Cross-Sector Batching
- The Pre-Commit Verification: A Discipline of Engineering Rigor in the cuzk Proving Engine
- The Final Review: A Code Diff Inspection Before Committing Phase 3 Cross-Sector Batching
- The Commit That Sealed Phase 3: Cross-Sector Batching for the cuzk SNARK Proving Engine
- The Commit That Bound Sectors Together: Phase 3 Cross-Sector Batching for the cuzk SNARK Engine
- The Verification Moment: Reading Git History as Architectural Narrative
- The Completion Signal: How a Todo Update Marks the Boundary Between Engineering Phases
- The Phase 3 Summary: A Milestone in Cross-Sector Batching for SNARK Proving
- "Proceed to Test": The Two-Word Pivot from Theory to Reality in the cuzk SNARK Engine
- The First Command: Why a Seasoned Engineer Runs `git status` Before GPU Testing
- The Testing Manifesto: How a Todo List Became the Blueprint for Validating Cross-Sector SNARK Batching
- The Reconnaissance Before the Benchmark: Validating Infrastructure for Phase 3 GPU Testing
- The Build That Validated a Pipeline: From Implementation to GPU E2E Testing
- The Threshold of Validation: A Pivotal Test Configuration in the cuzk Proving Engine
- The Threshold Moment: A Todo List as a Narrative Pivot
- The Memory Mandate: How a Single Sentence Shaped the Validation of a GPU Proving Engine
- The Pivot Point: A Single Bash Command That Revealed the State of a Proving Engine
- The Ghost Process: A Case Study in Engineering State Management
- The Critical Verification: Why a Simple `pgrep` Matters in GPU Benchmarking
- The Bridge Between Implementation and Validation: A Memory Monitor Script for Cross-Sector Batching
- The Quiet Permissions Step: How a Single `chmod` Enabled GPU Validation of Cross-Sector Batching
- The Baseline Before the Breakthrough: A Methodical Approach to Validating Cross-Sector Batching
- The Baseline Threshold: Validating Phase 3 Cross-Sector Batching Through Empirical Measurement
- The Moment of Truth: Launching the Baseline for Phase 3 Validation
- The Quiet Verification: Why a Simple `tail` Command Marks a Critical Milestone in SNARK Proving Engine Development
- The Waiting Game: SRS Loading as the Unsung Gatekeeper of Groth16 Proof Generation
- The Baseline That Proves the Batch: Validating Phase 3 Cross-Sector Batching for Filecoin SNARK Proving
- The Silence That Speaks: Understanding the Empty Message in AI-Assisted Coding Sessions