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Ray Serve Quiz ​

Multiple Choice Questions ​

  1. How does a Serve Deployment relate to a Kubernetes Deployment?
    • A) They are identical
    • B) It is a logical actor-replica unit, not one-to-one with Pods
    • C) Each replica requires one EC2 node
    • D) Serve does not use actors
Show Answer

Answer: B

One Ray Pod can host several replica actors.

  1. What is the 2.58.0 default proxy location?
    • A) Always one on the head
    • B) EveryNode on nodes hosting replicas
    • C) Every EC2 node unconditionally
    • D) Always Disabled
Show Answer

Answer: B

HeadOnly and Disabled are explicit choices. Distinguish stale architecture prose from the current API.

  1. How does the default deployment differ from num_replicas="auto"?
    • A) Both immediately start 100 replicas
    • B) Default fixed 1; auto applies min 1/max 100/target 2
    • C) Default GPU 1; auto GPU 100
    • D) Neither supports autoscaling
Show Answer

Answer: B

A directly constructed AutoscalingConfig defaults max to 1, so specify the intended bound.

  1. What is the max_queued_requests scope?
    • A) One cluster-global queue
    • B) Each caller, such as a proxy or handle
    • C) GPU KV-cache capacity
    • D) RayCluster Pod count
Show Answer

Answer: B

Default -1 is unlimited; exceeding a configured bound can reject HTTP requests or raise handle BackPressureError.

  1. Does a pending replica actor always create a new Pod and EC2 node?
    • A) Always one-to-one
    • B) No; existing capacity, group bounds, placement, and autoscaler enablement matter
    • C) It automatically becomes a CPU model
    • D) Serve directly creates EC2 nodes
Show Answer

Answer: B

Inspect actor placement, Pod size, and node provisioning separately.

  1. What was verified about 2.58.0 LLM backends?
    • A) Only vLLM exists
    • B) vLLM and SGLang backends exist; check their dependencies/configuration separately
    • C) Every engine kwarg is identical across engines
    • D) ray[serve]includes all LLM weights
Show Answer

Answer: B

Inference dependencies and model access/downloads are separate. CPU checks did not validate LLM execution.

  1. Which RayService update statement is accurate?
    • A) Mandatory for every EKS deployment with guaranteed no downtime
    • B) An optional lifecycle path; validate strategy, Gateway, capacity, readiness, and draining
    • C) Always only edits an existing Pod image
    • D) All long streams are always preserved
Show Answer

Answer: B

Distinguish application changes, cluster transitions, and actor reconfiguration.

  1. What did the local Echo test verify?
    • A) GPU performance
    • B) LLM quality
    • C) HTTP 200 and DeploymentHandle calls
    • D) Multi-node autoscaling
Show Answer

Answer: C

It was a tiny single-node CPU test without a model, LLM, GPU, or cloud deployment.

Short Answer Questions ​

  1. Why distinguish max ongoing, autoscaling target, and caller queue limit?
Show Answer

They control different things: requests assigned to replicas, target load for scaling, and waiting requests per caller. One setting does not establish all other bounds or latency guarantees.

  1. Why do cluster tokens or ClusterIP not complete application security?
Show Answer

Verify TLS, each entry point’s authentication/authorization, model-artifact permissions, sensitive request/log handling, and resource/queue/timeout policies separately.


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