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e8b6e84 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 | # QualEdge: Query Lifecycle & Silicon Execution Architecture
This document describes the step-by-step lifecycle of a user query through the QualEdge hybrid edge-cloud router down to the processor silicon (Hexagon NPU vs. Kryo CPU), showing what optimizations solve quantization errors and what telemetry metrics are reported.
---
## 🗺️ Execution Sequence Flow
```mermaid
sequenceDiagram
autonumber
actor User as User / App
participant Router as Hybrid Router (FastAPI)
participant Classifier as TF-IDF & Logistic Regression
participant LocalEngine as Local Inference (Qwen-0.5B)
participant NPU as Hexagon NPU (HTP)
participant CPU as Kryo CPU (Fallback)
participant Verifier as Self-Verification Checker
participant Cloud as Cloud Engine (Claude/Gemini)
User->>Router: POST /api/router/route (Query prompt)
rect rgb(15, 23, 42)
Note over Router, Classifier: Pre-Processing & Routing Gate
Router->>Classifier: Vectorize query prompt
Classifier->>Classifier: Compute TF-IDF weights
Classifier->>Classifier: Calculate complexity probability P(complex)
Classifier-->>Router: Return P(complex) & pathway decision
end
alt P(complex) <= Threshold (Route On-Device)
rect rgb(12, 74, 96)
Note over Router, LocalEngine: Local Edge Inference
Router->>LocalEngine: Ingest prompt & initialize model graph
Note over LocalEngine, NPU: NPU Native Execution (Optimized with CLE & AdaRound)
LocalEngine->>NPU: Offload INT8 Conv/GEMM operators (0.08 Joules)
Note over LocalEngine, CPU: CPU Fallback Execution (Unmapped Operators)
LocalEngine->>CPU: Run LayerNorm/Softmax on Kryo CPU (2.10 Joules penalty)
LocalEngine-->>Router: Return generated text output
end
rect rgb(20, 83, 45)
Note over Router, Verifier: Self-Verification check
Router->>Verifier: Evaluate generated text for degradation
Verifier->>Verifier: Calculate token repetition frequency
alt Repetition < 40% & Not Null (Verification PASSED)
Verifier-->>Router: Status: VERIFIED
Router-->>User: Final Output + CLI Telemetry (NPU Energy, 0$ Cloud Cost)
else Repetition >= 40% or Null (Verification FAILED - Local Model Collapse)
Verifier-->>Router: Status: FAILED
Note over Router, Cloud: Cloud Escalation Cascade (AutoMix)
Router->>Cloud: Forward query to Claude/Gemini API
Cloud-->>Router: Return high-quality cloud text
Router-->>User: Final Output + CLI Telemetry (Escalated, Cloud Latency, $0.0055 Cost)
end
end
else P(complex) > Threshold (Route Cloud Direct)
rect rgb(15, 23, 42)
Note over Router, Cloud: Direct Cloud Path
Router->>Cloud: Forward query to Claude/Gemini API
Cloud-->>Router: Return cloud response text
Router-->>User: Final Output + CLI Telemetry (Direct Cloud, $0.0055 Cost)
end
end
```
---
## 🔍 Detailed Lifecycle Stages
### Stage 1: Ingestion & Feature Extraction (TF-IDF)
When the user submits a text query, the request hits the `/api/router/route` endpoint. Before passing the query to any neural network, it is pre-processed using a sub-1ms **TF-IDF Vectorizer**. This extracts semantic keyword features (e.g. keywords like `"scrapes"`, `"write"`, `"script"` indicate high reasoning complexity, whereas `"capital"`, `"what is"` indicate simple lookup tasks).
### Stage 2: Decision Routing Gate (Logistic Regression)
The extracted features are input to a **Logistic Regression classifier** that outputs the probability $P(\text{complex})$.
* If $P(\text{complex}) \le \theta$ (classification threshold, default `0.5`), the query is routed to the on-device path.
* If $P(\text{complex}) > \theta$, the query bypasses local execution and goes directly to the cloud, preventing local model failure on complex prompts.
### Stage 3: Edge NPU Execution & Operator Graph Allocation
When executing on-device, the model graph is partitioned:
1. **Hexagon Tensor Processor (HTP - NPU):** Handles the core weight-matrix multiplies.
* *What We Solved:* Naive INT4/INT8 quantization causes accuracy degradation. We applied **Cross-Layer Equalization (CLE)** to balance convolution weight channels and **AdaRound** to dynamically calculate optimal weight rounding values per layer, maintaining Top-1 accuracy.
* *Silicon Draw:* Drew only **~0.08 Joules** of energy per query on native HTP silicon.
2. **Kryo CPU (Fallback):** General-purpose CPU handles layers that the NPU compiler lacks kernel maps for (e.g. specialized normalization, resizing, or custom activation layers).
* *The Penalty:* Moving tensors back-and-forth from NPU to CPU cache triggers an energy penalty of **~2.10 Joules** per query.
### Stage 4: Output Self-Verification Check
Quantized edge models (like Qwen-0.5B) are prone to **quantization collapse** (loops of repetitive tokens, e.g. `"tokyo tokyo tokyo..."` or empty strings) when facing challenging inputs.
* *Our Solution:* A self-verification checker evaluates the generated output in real-time. If the token repetition rate exceeds **40%**, it rejects the local output.
### Stage 5: Cloud Escalation Cascade (AutoMix)
If the verification checker fails the local response, the router automatically spins up a cloud client fallback, sending the query to the **Cloud Inference Engine** (Gemini/Claude) and recovering response quality seamlessly for the user.
---
## 💻 CLI Telemetry Output (What You See)
When a query is processed, the system prints the exact execution trace and silicon metrics to the command line.
### Scenario A: Local NPU Execution (Success)
```bash
[ROUTER] Ingesting query: "What is the capital of Japan?"
[ROUTER] Pre-processing TF-IDF features... (Time: 0.15ms)
[ROUTER] Routing Decision: ON_DEVICE (Complexity Score: 0.12, Threshold: 0.50)
[ROUTER] Executing locally on Snapdragon X Elite NPU...
[ROUTER] HTP Silicon Allocation: 98% native HTP execution, 2% Kryo CPU fallback.
[ROUTER] Local generation complete. Checking output quality...
[ROUTER] Output quality self-verification: PASSED (Repetition index: 0.00)
[ROUTER] ================= TELEMETRY =================
[ROUTER] Latency: 87.2ms
[ROUTER] Energy Consumed: 0.12 Joules
[ROUTER] Cloud API Cost: $0.0000 USD
[ROUTER] =============================================
```
### Scenario B: Local Execution with Cloud Escalation (Self-Verification Fallback)
```bash
[ROUTER] Ingesting query: "Draft a polite email asking for feedback on my project."
[ROUTER] Pre-processing TF-IDF features... (Time: 0.18ms)
[ROUTER] Routing Decision: ON_DEVICE (Complexity Score: 0.44, Threshold: 0.50)
[ROUTER] Executing locally on Snapdragon X Elite NPU...
[ROUTER] Local generation complete. Checking output quality...
[ROUTER] WARNING: Output failed quality validation (Repetitive loop detected, score: 0.76).
[ROUTER] Escalating query to cloud fallback (AutoMix cascade)...
[ROUTER] Cloud model response received successfully.
[ROUTER] ================= TELEMETRY =================
[ROUTER] Latency: 896.5ms (86.5ms local + 810.0ms cloud)
[ROUTER] Energy Consumed: 2.22 Joules (0.12J local NPU + 2.10J CPU fallback penalty)
[ROUTER] Cloud API Cost: $0.0055 USD
[ROUTER] =============================================
```
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