{"paper":{"title":"Microarchitectural Co-Optimization for Sustained Throughput of RISC-V Multi-Lane Chaining Vector Processors","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"Microarchitectural fixes to memory, control, and operand paths in the Ara RISC-V vector processor deliver a 1.33x geometric-mean speedup and close 12.2% of the roofline gap without added bandwidth or hardware.","cross_cats":[],"primary_cat":"cs.AR","authors_text":"Weiying Wang, Zhiwei Zhang","submitted_at":"2026-04-24T07:47:20Z","abstract_excerpt":"Modern RISC vector processors rely on multi-lane parallelism and chaining to achieve high sustained throughput, yet practical execution often deviates from the ideal reference due to microarchitectural inefficiencies. This work targets the open-source RVV processor Ara and analyzes its sustained-throughput loss under a fixed hardware configuration. We first establish an ideal multi-lane chaining model that decomposes ideal execution into prologue startup, steady-state progression, and tail drain, and uses this reference to characterize real-execution deviations. Based on this model, we attribu"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"Experimental results show that, without increasing raw memory bandwidth or changing the main processor configuration, Ara-Opt achieves a geometric-mean speedup of 1.33x over baseline Ara. Under roofline-based normalization, the geometric-mean gap-closed ratio reaches 12.2%.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"That the proposed microarchitectural optimizations can be implemented in the Ara design without increasing hardware resources or altering the main processor configuration, and that the ideal multi-lane chaining execution model accurately captures the theoretical performance bound for comparison.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"Co-optimized microarchitecture for the Ara RISC-V vector processor delivers 1.33x geometric mean speedup over baseline by addressing data supply, dependence management, and operand delivery inefficiencies.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"Microarchitectural fixes to memory, control, and operand paths in the Ara RISC-V vector processor deliver a 1.33x geometric-mean speedup and close 12.2% of the roofline gap without added bandwidth or hardware.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"9df53eb4a22a79d79144e561d05e79f6060ec301dc9aec6d2feec1ce81365314"},"source":{"id":"2604.22314","kind":"arxiv","version":2},"verdict":{"id":"8316db9b-e685-40fa-b280-001dadfb1e12","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-08T09:23:12.179877Z","strongest_claim":"Experimental results show that, without increasing raw memory bandwidth or changing the main processor configuration, Ara-Opt achieves a geometric-mean speedup of 1.33x over baseline Ara. Under roofline-based normalization, the geometric-mean gap-closed ratio reaches 12.2%.","one_line_summary":"Co-optimized microarchitecture for the Ara RISC-V vector processor delivers 1.33x geometric mean speedup over baseline by addressing data supply, dependence management, and operand delivery inefficiencies.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"That the proposed microarchitectural optimizations can be implemented in the Ara design without increasing hardware resources or altering the main processor configuration, and that the ideal multi-lane chaining execution model accurately captures the theoretical performance bound for comparison.","pith_extraction_headline":"Microarchitectural fixes to memory, control, and operand paths in the Ara RISC-V vector processor deliver a 1.33x geometric-mean speedup and close 12.2% of the roofline gap without added bandwidth or hardware."},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2604.22314/integrity.json","findings":[],"available":true,"detectors_run":[{"name":"ai_meta_artifact","ran_at":"2026-05-21T10:42:16.225709Z","status":"completed","version":"1.0.0","findings_count":0},{"name":"doi_compliance","ran_at":"2026-05-20T00:06:02.317705Z","status":"completed","version":"1.0.0","findings_count":0}],"snapshot_sha256":"178b1c55a91ec61849dfb752ef233e7b9c4bf5f96f9c2e31446c818659976d13"},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}