Temporal Shifting: Scheduling Compute Against Time
Time is the cheapest axis to move on. Shifting a job by an hour costs nothing but patience, and the grid's price and carbon curves swing wildly across a single day. A deferrable job run at 3 a.m. on wind can cost a fraction of the same job run at 6 p.m. on gas peakers, and emit a fraction of the carbon, with identical output. Temporal shifting is the highest-return, lowest-risk technique in the toolkit because it keeps the work in the same building on the same chips. The only thing that changes is the clock. Master the queue's relationship to time before you ever touch geography.
Knowledge check
Why is temporal shifting generally lower-risk than moving workloads between regions?
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Temporal shifting keeps a job in the same facility on the same hardware and only changes when it runs, so it avoids data transfer, replication, and latency penalties. The main cost is delay, bounded by the job's deadline, whereas spatial shifting adds network movement and data-gravity constraints.