Every CPU Cycle Counts

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" summary

A compact on‑chip trace encodes cycle‑accurate retirements as run‑length pairs and triplets using Elias gamma encoding and five count tokens called tokens A–E, plus an optional D/E mode that emits per‑cycle instruction counts for multi‑issue cores. A stall amortization option treats short stalls as retirements to cut trace volume, an example dropping from about 2.0 bits/instruction to 1.4 bits, while D/E reaches ~1.25 bits with full precision. This encoder plugs into a non‑intrusive SOC monitor and message fabric and feeds runtime anomaly and causality analytics.

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" chapters (14)

1. 0:00Intro
2. 0:21Understanding Complex Systems
3. 1:23CPU Stalling Behavior
4. 2:03Retirement Delta Trace
5. 3:50Variable Length Encoding
6. 5:21CPU Core and Trace Encoder
7. 6:31Number Tokens
8. 7:31Example
9. 9:05Stall amortization
10. 11:02Multiissue CPU
11. 12:18DNE Token
12. 13:21Algorithm
13. 15:24Trace System
14. 19:01Summary

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