A platform team is migrating containerised inference services to a Kubernetes cluster that has GPUs. Multiple small inference replicas each need a fraction of a single GPU rather than an entire device. Which approach best enables multiple pods to share one physical GPU on that cluster?
- ARequest multiple CPU cores per pod and rely on the GPU driver to time-share the device automatically across pods
- BSet Kubernetes CPU and memory requests per pod and let the default scheduler bin-pack the inference replicas onto the GPU node with no GPU-sharing driver
- CDeploy a fractional GPU scheduler such as Run:ai or NVIDIA MIG, which partitions the GPU and exposes sub-GPU resource fractions to the Kubernetes scheduler Correct
- DSet resource requests to zero for the GPU field so pods schedule freely, then configure a node taint to attract only inference workloads
Why A is wrong: Standard GPU drivers do not automatically time-share a GPU across independent processes in proportion to pod CPU requests. Without an explicit partitioning or virtualisation layer, each pod would attempt to use the full device, causing contention.
Why B is wrong: CPU and memory requests constrain only host resources; they do not partition or arbitrate the GPU. With no GPU-sharing driver the default scheduler still treats the GPU as one indivisible device, so the first pod claims it and the remaining replicas are starved or fail to schedule.
Why C is correct: Fractional GPU schedulers extend the Kubernetes device-plugin model to advertise sub-GPU resources. Run:ai intercepts scheduling and enforces GPU memory and compute quotas per pod. NVIDIA Multi-Instance GPU (MIG) partitions a physical GPU into independent instances with dedicated memory and compute slices, each schedulable as a distinct Kubernetes resource.
Why D is wrong: Setting GPU requests to zero causes the Kubernetes scheduler to ignore GPU availability entirely; pods would be placed without any GPU allocation or enforcement, leading to uncontrolled device access and potential out-of-memory failures.