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StarSling runner benchmarks, hidden CPU model, and rates

The StarSling sample is a Linux x64 job using its explicit two-vCPU label. It reports the AMD EPYC family, but the guest hides the exact model. StarSling describes its current fleet as fifth-generation EPYC. That is useful family context, but it doesn't turn a masked model string into proof of a particular SKU on the measured host.

By TechCompare · Updated

Measured configurations
1
CPU execution threads
1
Five accepted samples per runner

The explicit label matters

StarSling lists $0.004 per minute for the two-vCPU runner used here, or $0.002 per vCPU-minute. Its bare Ubuntu label defaults to four vCPUs, so substituting that rate would price a different request. The published ladder reaches 64 vCPUs. Only the two-vCPU label appears in these results, which leaves scaling at larger sizes unmeasured.

Hardware tests don't measure workflow optimization

A provider may also offer changes to sharding, dependency caching, and workflow scheduling. The supplied suite measures CPU, disk, cache transfers, and one internet endpoint. It doesn't apply optimization suggestions to a repository or measure their effect on the build's critical path. Keep those separate from the observed performance of the requested runner.

Calculator

GitHub Actions runner CPU models, single thread CPU scores, disk, cache, and internet scores, and value per USD compute cost. Missing tests have no score.
RunnerCPUSingle threadCPU valueDiskCacheInternetCost/vCPU/minUSDMax vCPU
StarSling Linux x64

AMD EPYC (model hidden)

38,218
19.1M/USD
559.1
101
116.3
0.00264

Single thread CPU: CoreMark iterations/s. Disk and cache: composite MiB/s. Internet: composite Mbps. Value: score ÷ USD cost/vCPU/min. K means thousand, M means million. Higher is better. Cache uses each runner's best tested cache or artifact backend. Limits: maximum runner vCPU. Prices and value use USD. RunJob's EUR rate is converted at €1 = $1.1206 (ECB, 2026-10-09).

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Measurement context

This result uses a single pinned execution thread. The CPU score is a median across five samples, with the full observed range and variation available in the details. Disk, cache, and internet scores use fixed formulas that stay unchanged when another runner is added.

Verdict

Keep hardware certainty visible when comparing providers. The guest and the pricing documentation answer different questions. Use the benchmark to inspect observed behavior, and use the provider's rate table to identify the product you can buy.

More runner benchmark scenarios

Frequently asked questions

Are these independent GitHub Actions runner benchmarks?
TechCompare publishes measurements from its own runner benchmark suite. The results come from the supplied published reports, while provider documentation supplies hardware mappings, prices, and available sizes. Scores from provider marketing pages aren't used as test results.
Does a CoreMark score predict my build time?
No. CoreMark is a CPU microbenchmark running one execution thread. A full build also depends on parallelism, memory, disk, dependencies, cache behavior, and queue time. This snapshot doesn't measure complete application builds or queue delays.
How are disk, cache, and internet scores calculated?
Each score is a geometric mean of that runner's own measurements. Disk combines sequential read/write MiB/s with random read/write IOPS converted to MiB/s using the 4 KiB operation size. Cache combines save and restore MiB/s from one backend. By default, each runner uses its highest verified score across tested cache and artifact backends. Hover or open details to see the backend, or select a specific backend type. Internet combines available download and upload Mbps, or uses the single recorded direction. Protocol 7 reports speeds from actual payload bytes and elapsed time, including transfers that reach the time limit. Older timeout records use recorded bytes divided by the nominal limit. These fixed formulas have no ranking reference or upper score limit, so adding a faster runner doesn't change existing scores. CPU keeps its measured CoreMark iterations per second.
How is price per minute per vCPU calculated?
A fixed runner's quoted minute rate is divided by its billed vCPU count. Prices are shown in USD and are list or overage rates before allowances and extras. RunJob publishes EUR consumed CPU rates, which are converted using the dated ECB reference rate shown on the page. Its original rate stays in the details, and memory charges are additional. GitHub uses private standard rates, and Namespace shows overage with prepaid equivalents.
What does CPU value mean?
CPU value is the measured single thread CoreMark score divided by the USD cost per vCPU per minute. More billed vCPUs don't multiply the measured score. EUR compute rates are converted before calculating value, so every provider is in one USD ranking. K means thousand and M means million. Optional disk, cache, and internet value columns use the same score divided by rate formula. These ratios don't measure full build performance or predict the final bill.
Why is an exact CPU model sometimes missing?
Some virtual machines expose only AMD EPYC or aarch64. The table uses a provider mapping where documentation identifies a family, labels that evidence, and leaves undisclosed model numbers unconfirmed. Similar benchmark scores aren't enough to identify a processor.
Are missing tests counted as zero?
No. Internet transfers with a nonzero recorded byte count can supply a speed even if they reach the time limit. A blocked request or a timeout with no recorded bytes stays unscored. Disk uses verified sample medians with all four throughput components. The updated BuildPulse ARM disk result is included using its three completed samples, with the original counts in the details. Cache requires all three verified save and restore pairs. The table shows a dash when no score is available. Hover or open the row details to inspect the measurements.