Choose an evaluation Guide
A Guide is a deployment recipe. Choose one in the configuration editor, then run an evaluation to measure it. Start with Optimized Baseline before testing a more specialized option.
Choose the experiment
| What you want to test | Guide | What to compare |
|---|---|---|
| General routing and prefix reuse | Optimized Baseline | Full Guide versus load-only |
| Separate input processing from token generation | PD Disaggregation | P/D versus an aggregated deployment with the same accelerator budget |
| Route repeated prompts to instances that cache them | Precise Prefix Cache Routing | Precise versus Optimized Baseline |
| Reuse cached prefixes that no longer fit in device memory | Tiered Prefix Cache | CPU offload versus HBM-only baseline |
Create a Guide configuration
- Open Evaluation → New Task → Deploy configurations → Create configuration.
- Choose the cluster, model and cache storage.
- Under Guide template, select Guide, Accelerator and the available variant.
- Set replicas and tensor parallel size. Keep advanced settings unchanged for the first run.
- Click Generate YAML. If currently available cards are insufficient, review the red warning and physical card total. When the physical total is sufficient, click Continue & generate; deployment may remain Pending until enough cards are available. Otherwise, reduce replicas / TP.
- Correct any highlighted errors, review the configuration, and save it.
- Return to the evaluation task, select the configuration and set the workload.
When changing cluster or source version, recheck the available variants. If generation reports missing network or storage resources, choose another supported variant or ask the cluster administrator to prepare those resources.
Test Optimized Baseline
- Select optimized-baseline in Guide.
- Keep the same replicas and TP for the candidate and its comparison.
- Select the Full Guide and load-only comparison when offered.
- In the task dialog, use Add rate ramp to send repeated prefixes (Prefix cache reuse in the full wizard).
- Compare TTFT, throughput and success rate. Lower TTFT at the same load shows faster responses.
To isolate the effect of load scoring, add affinity-only. It keeps prefix affinity and saturation protection but removes load scoring.
Test P/D disaggregation
- Select pd-disaggregation and a P/D Guide variant.
- Set Prefill replicas, Prefill tensor parallel size, Decode replicas, and Decode tensor parallel size.
- For vllm-rdma, check Cache & network → RDMA NICs per pod with your cluster administrator.
- Add an aggregated baseline using the same total number of accelerators.
- Use Add matrix to test the input/output sizes your application needs (Fixed input / output lengths in the full wizard).
- Compare TTFT and TPOT as well as throughput. Faster token generation can still come with a longer wait for the first token.
Count resources on both sides: one Prefill replica at TP 2 plus two Decode replicas at TP 1 uses four accelerators. Keep that total fixed when comparing P:D ratios.
Test precise prefix-cache routing
- Create a precise-prefix-cache-routing configuration.
- Add optimized-baseline as a comparison using the same model, replicas and TP.
- Keep the tokenizer and block-size settings consistent between configurations.
- Use Add rate ramp (Prefix cache reuse in the full wizard) with the same prefix groups and load stages.
- Compare measured TTFT, throughput and engine cache reuse.
Router cache estimates are not measured engine reuse. Use the engine measurements when deciding whether the configuration reduced repeated computation.
Test tiered prefix cache
- Create a tiered-prefix-cache configuration with HBM-only baseline.
- Create another with Native CPU offload or LMCache CPU offload from the variant list.
- Under Cache & network, set CPU cache capacity per pod (GiB) within the node's available host memory.
- Save both configurations and select them in one evaluation.
- Use Add rate ramp (Prefix cache reuse in the full wizard) with repeated prompts. Compare TTFT, throughput, CPU memory use and cache restore activity.
The configuration editor supports CPU offload, not filesystem offload. If the repeated prefixes already fit in device memory, increase the prefix groups or shared-prefix length to test whether CPU caching helps under pressure.
Keep comparisons fair
Use the same model version, runtime image, resource budget, workload and SLO for both sides, changing only the feature being tested.
| Comparison option | What it changes |
|---|---|
| direct-vllm | Runs a separate plain-vLLM deployment |
| router-neutral | Removes specialized routing; it is not strict round-robin |
| load-only | Keeps load-aware routing without prefix affinity |
| affinity-only | Keeps affinity without load scoring |
| kubernetes-service | Uses the candidate's existing pods while bypassing its inference router |
Cache is retained between load stages and same-pod comparisons. Do not label a later stage a cold-cache test. Compare matching load points, and check missing-data messages rather than treating absent metrics as zero.
If KV working-set metrics are unavailable, read the collection reason in the result. Benchmarks do not install a missing probe into an existing service. Collection requirements are in the Evaluation API reference.