Source: https://guthlabs.ai/docs/instruments/cpu-cache-hit-rate-amat-calculator/implementation/

instrument implementation / implementation-contract

# CPU Cache Hit-Rate / AMAT Calculator implementation

A source-bound implementation contract for CPU Cache Hit-Rate / AMAT Calculator; deployment and executable qualification remain separate.

Status: **VERIFIED_CLEAN**Lifecycle: **implementation-contract**

## Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

**Record owner**: Guth Instruments

**Lifecycle**: verified-clean

**Evidence ID**: t4-288

**Effect**: Computation or source lookup only

## Input and validation requirements

The extreme-magnitude vector overflows finite JavaScript arithmetic to Infinity, and the convention probe produces radically different results unless percentage versus fractional miss-rate input is explicitly disambiguated.

## Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

## Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

````
{
  "inputs": {
    "levels": 1,
    "hit_time_ns": 1,
    "miss_rate": 0.05,
    "miss_penalty_ns": 80
  },
  "expected_outputs": {
    "amat_ns": 5,
    "effective_speedup_vs_no_cache": null
  },
  "working": "AMAT = hit_time + miss_rate × miss_penalty\n= 1 ns + 0.05 × 80 ns\n= 1 ns + 4 ns\n= 5 ns.\nSpeedup is unavailable because no no-cache baseline is specified."
}
````

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/cpu-cache-hit-rate-amat-calculator/>)[02**Mechanism**](<https://guthlabs.ai/docs/instruments/cpu-cache-hit-rate-amat-calculator/mechanism/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/cpu-cache-hit-rate-amat-calculator/qualification/>)

## Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

- `VERIFIED_LEDGER.json`

- `evidence-tranche4/tranche4-results.json`