GPU Utilization Safety Buffer Planner

Size the standby capacity your GPU fleet needs to stay on track. Provide your utilization target and monthly interruption hours, then optionally layer in schedulable GPU-hours and blended pricing to reveal headroom percentage, GPU-hours to reserve, and the incremental spend required to absorb downtime without missing SLAs.

Desired average GPU utilization after factoring in maintenance, preemption, and queue delays.
Total downtime hours from preemption, maintenance, or congestion that cut into runtime each month.
Defaults to 720. Override with the schedulable GPU-hours across your fleet and month length.
Blend reserved, on-demand, and managed service pricing to capture the true hourly cost.

Examples

  • 93% target utilization, 18 downtime hours, 744 schedulable hours, $2.10 blended rate ⇒ Requires 71.43 GPU-hours of headroom (9.60%), $150.01 USD monthly buffer cost, and delivers 84.85% effective utilization after downtime.
  • 88% target utilization, 32 downtime hours, 720 schedulable hours, no cost input ⇒ Recommends 122.76 GPU-hours of buffer (17.05%) split between 86.40 baseline slack and 36.36 replacement hours, resulting in 75.18% effective utilization.

FAQ

How should I treat autoscaling groups?

Use the minimum replica hours you keep idle as part of schedulable hours and track interruption hours on the active replica pool to size additional standby nodes accurately.

Do reservation or committed-use discounts change the math?

Yes. Update the blended rate to include discounts or spot mixes so the buffer cost reflects your actual procurement strategy.

Can I budget downtime separately for training and inference clusters?

Run the calculator twice with workload-specific utilization targets and downtime assumptions, then aggregate the GPU-hour buffers if the fleets share capacity.

What if I track downtime in minutes instead of hours?

Convert minutes to fractional hours before entry—for example, 90 minutes becomes 1.5 hours—so the buffer output aligns with the GPU-hour units used in capacity planning.

Additional Information

  • Baseline slack equals schedulable hours multiplied by 1 minus the utilization target, representing idle capacity already assumed in the goal.
  • Downtime replacement hours gross up outages by dividing downtime by the utilization target so lost production is replaced one-for-one.
  • Headroom percent divides extra GPU-hours by schedulable hours to show how much standby capacity the fleet needs to meet the goal.
  • If you supply a blended rate, the calculator multiplies buffer hours by cost per hour to highlight the monthly expense of protecting SLAs.

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