mig

MIG carves an H100 into up to seven hardware slices with their own SMs, memory and bandwidth; MPS lets processes share one SM pool through a single context. One gives fault and performance isolation at a fixed slice size; the other gives flexibility and a shared failure domain. The numbers that decide it.

The part with no NVLink can be the correct choice, and the reason is the workload shape rather than the specification. What fits on one card, what MIG partitioning buys a multi-tenant service, and the exact point where the missing scale-up link makes the decision flip.

Hardware partitions, shared SMs, and context switching are three different promises about isolation and waste. The slice arithmetic for an H100, what each mode gives up, and the one rule about tenants that decides most of it.

Fractions are either hardware slices with fixed shapes or soft shares with no isolation, and the scheduler has to know which. The representation, the packing score, the fragmentation arithmetic that spread placement produces, and the defragmentation step that fixes it.

Device plugins count GPUs and know nothing else; Dynamic Resource Allocation lets a pod ask for devices by attribute and share them by claim. What the two models can and cannot express, what DRA changes for MIG, NVLink domains and multi-node gangs, and a migration stance for a fleet that runs both.

A notebook holds a GPU for eight hours and uses it for twenty minutes, which is what sharing is for and what makes it hard. The sharing mode to pick and the one to refuse across users, the idle-reclaim loop that keeps sessions alive without holding hardware, the quota arithmetic, and how many GPUs 300 users need.