Source

CoreWeave (2025), LIT-222 — a benchmark report that fits a right-censored exponential survival model to real job durations and interruptions.

The two facts that decide the interval

Expected loss is half the interval. From the report: “assuming a failure can occur randomly anywhere in the inter-checkpoint interval, the expected badput for any job is half the inter-checkpoint interval.” So doubling the cadence halves the work at risk, and the benefit of checkpointing more often is linear and knowable rather than a matter of taste.

Failure rate scales with the job. Synchronous data-parallel training is all-or-nothing, so a job’s mean time to failure is the per-GPU rate divided by its GPU count. The measured per-GPU rate is 3,748.25 days per failure, giving 3.66 days at 1,024 GPUs — and, on the same model, under a day at 4,096 and a few hours at 16,384.

That second fact is the recommendation. An interval that is right for a 256-GPU job is four times too long for the same work at 1,024 GPUs, and the run will not tell you: it simply loses more each time, and the loss is charged to “infrastructure flakiness” rather than to a setting nobody revisited.

What this is an alternative to

SOTA-054 derives the interval from the write cost, adapting it to hold checkpointing overhead inside a bound. That is the cost side. This is the risk side, and the two are the halves of one trade — checkpoint often enough that expected loss is small, rarely enough that the writing is not the job.

Neither source combines them. The classical answer given both is an interval of about √(2 · checkpoint cost · MTTF); the record holds no source for that result, which is worth stating rather than deriving here.

The practical reading, with both practices in hand: take the write cost from profiling as SOTA-054 says, take MTTF from the fleet’s own failure data as this one says, and expect the answer to move when the job is resized — which is the part neither the checkpointing literature nor most operators do.

What to discount

A vendor’s benchmark of its own platform, with baselines it selected. DP-005 applies: the uplift figures are marketing and the ratios are not independent evidence.

The method and the shape survive that. A censored survival fit is the right way to estimate a failure rate from a fleet where most jobs do not fail, and MTTF falling linearly in job size is structural. The constant is one fleet’s and should be re-measured, which is exactly what makes this a practice about measuring rather than a practice about 3.66 days.