SA260324R-0060::SPLIT04

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① SA Source

Context Before

SRAM and Memory Hierarchy

We have written about the role of SRAM in the memory hierarchy, but the quick recap is that SRAM is very fast (low latency and high bandwidth) but this comes at the expense of density and therefore cost.

Evidence

SRAM machines such as Groq’s LPU therefore enable very fast time to first token and tokens per second per user but at the expense of total throughput, as their limited SRAM capacity quickly gets saturated by weights, with little left over for KVcache that grows as more users are batched. GPUs win for throughput and cost as we have shown. This is why Nvidia has decided to combine these architectures to get the best of both worlds: accelerate parts of decode that are more latency sensitive and are not as memory heavy on a low-latency SRAM-heavy chip like the LPU, while memory hungry attention is performed on GPUs that come with a lot of fast (but not SRAM fast) memory capacity.

Context After

image

Source: SemiAnalysis

② Atomic Claim

隨著 batch 中的使用者增加,KV cache 的容量需求會成長。

  • Epistemic Mode: ASSERTED
  • Mapping Status: COMPLETE

③ Semantic Frame

{
  "attribute": "CAPACITY_GROWTH_WITH_BATCHED_USERS",
  "context_nodes": [],
  "entity": {
    "id": "04_knowledge_base/KV cache",
    "label": "KV cache"
  },
  "frame_type": "ATTRIBUTE",
  "qualifiers": {
    "condition_text": "as more users are batched",
    "numeric_mentions": [],
    "temporal_mentions": []
  },
  "value": {
    "numeric_mentions": [],
    "value_text": "KV cache grows as more users are batched"
  }
}

④ Canonical Entity Mapping

RoleSurface LabelCanonical Target
entityKV cache04_knowledge_base/KV cache

⑤ V2 Draft(需要修正時直接編輯)

Inline repair

只編輯以下三個 Draft 區塊。完成後將 review_action 設為 REQUEST_REPAIR,再手動執行 Repair Preview。
執行腳本前,Draft 不會寫入 Claim Store 或 Graph。

V2 Atomic Claim Draft

隨著 batch 中的使用者增加,KV cache 的容量需求會成長。

V2 Semantic Frame Draft

{
  "attribute": "CAPACITY_GROWTH_WITH_BATCHED_USERS",
  "context_nodes": [],
  "entity": {
    "id": "04_knowledge_base/KV cache",
    "label": "KV cache"
  },
  "frame_type": "ATTRIBUTE",
  "qualifiers": {
    "condition_text": "as more users are batched",
    "numeric_mentions": [],
    "temporal_mentions": []
  },
  "value": {
    "numeric_mentions": [],
    "value_text": "KV cache grows as more users are batched"
  }
}

V2 Revision Metadata Draft

{
  "epistemic_mode": "ASSERTED",
  "mapping_status": "COMPLETE"
}

⑥ Human Review

請在 Properties 逐項確認:

  • 原文 → Atomic Claim 是否忠實
  • Atomic Claim → Semantic Frame 是否忠實
  • Canonical Entity mapping 是否正確
  • Epistemic mode 是否保留原文語氣
  • 最後選擇 review_action

Review state

Markdown 內文不是正式 approval。只有 Apply bridge 寫入的 Decision Ledger event 才是正式決策。